So what you are telling me is that it's easy to:
- plan the editorial calendar
- put together the article outlines that you give the writers
- round up the artists and arrange meetings
- view art while it's being developed
- coordinate and manage the writers and artists
- meet with the editors
- edit the articles
- put the articles together in layout
- edit again to manage the whitespace
- deal with the late article that comes in and requires more editing
- order another piece of art because you need to swap out an image (for whatever reason)
- get it to final sign-off
- (Press Print to PDF)
- pass the new crunch to DDI team
- roll out articles on Dungeon and Dragon online
And this is an incomplete list.... This is not easy.
Or did you mean that it was easy to:
Because, yes, this is easy.
I have altered your post to number your list for ease of expounding on it.
1- Yes planning the editorial calendar should be easy as you are basically taking what is in the magazine and has already been decided what will be in it and breaking it up into which article to release live on what days. Likewise the entire system can be ready in advance to release the articles on time and not have to wait to program the CMS with each new article on the day it is to be released. If the software running the website cannot do date checking then I would suggest getting new software to handle proper dispersal of the material. So if you already know what is going into the magazine in advance, then you can easily create the article calendar.
2- Druid playtest. We want 3 levels for subscribers. That doesn't seem to hard to say, or get someone to just gather the data from the design team and stick it in the magazine. Again the complete magazine should be done before release time of any article on DDI. You should know in advance which playtest or anything else you will need and put them into it and be ready ahead of time.
3- The art must be done well in advance. So again if you know what art you need for an article, then you already know what article you are going to have for the issue. Most of the gaudy banners and borders for the articles already exist and are just plug and play.
4- This goes with #3. The art like the articles needs to be done in advance of the month the articles will be released. Again see the physical book publishing methods.
5- You don't need to coordinate the artist and writers. You need to give the artists a piece and a deadline to create. X number of missed deadlines means the artist is looking for a new job. Same for the writers. This again is why you do these things in advance because you aren't working on a newspaper and an entire publication must be scrapped and changed at the last minute.
6- The editors need the entire issue to work on so they can not only fix the flow of the articles, but the typos and other things that people normally think about. Do you want the RPGA article before or after the playtest this month? Again this is why you do the issues in advance of the month they are being created for to give ample time to be put online and for corrections to be made to the overall PDF, that will be split into individual files for the individual article releases over the course of the calendar.
7- This should be being done as the articles are written. writer gets task to write article, editor edits it and submits it to publishing and they start mocking up the pages for the article since all articles now start on a new page without this whole "(continued on page 80)" bit of the past. Layout is much easier now due to technology.
8- see above.
9- WotC doesn't do this very well, so I don't see why even bother dicussing it. Have you seen the DDI articles and even the printed books at all the wasted real estate space creating that whitespace that could be used to beter reduce the cost of printing and even with PDFs, reduce the filesize to reduce the cost of bandwidth? WotC does not mangage whitespace, they just let it exist without consideration of it. So no lost time on this task.
10- This is why you do the issue a month in advance. It isn't a daily publication that requires the latest world news like the DOW Jones index in an article, so you have time to do it in advance. You know what classes are coming out for playtests, so just take what exists for the book coming out in February and get one of those classes in the February issue of Dragon. Dungeon submissions have even more time they can be done because submissions have to be planned out where they best fit. Scales of War for example needed a firm plan and at least 4 months advance work prior to publishing the first one so that playtesting could be properly done to make sure things worked the way they were supposed to on part A before you printed it so you could make changes to part B and all subsequent parts without causing a delay in the article itself.
11- This is where you order extra art to begin with and have some on hand that has not yet been used for that filler piece, or the piece needs changes for some reason, because painting something isn't an overnight process, and it seems not all the artists work solely in digital media and vector graphics.
12- The editor-in-chief should have been signing off on the pieces as they come in.
13- ....
14- once the PDF is made it takes minutes to split the compiled issue into individual articles. Just name then the way the DDI team needs them named for CMS and send each individual article and the finished issue to them to place on the servers.
15- This is what the server does. Is date >= 12/17/08? Archive shows DDI #18 in the list, DDI #18 now is allowed access to via port 80 requests rather than sending the page output that the article is not ready yet. This should all be done prior to the last day of the previous month, and the DDI team should know what they are getting in advance to set up the content management system with proper dates for things for the database to release the new information on the correct dates. Have you ever sen a webcomic? You can easily place comics well in adavance of the release date and just let the software handle releasing the newer ones on time rather than having to update it with each new comic strip on the day of release. Computers can check a date and run a script that gets the proper information to display new material. Technically you could have a lot of the release dates and information planned into the system in advance, and the DD Insider articles should be since they are a weekly occurrence.
It is easy if done correctly, but many people this day thanks to technology think they can do anything because they have the software to aid them do it, but don't know how to do it and forget a few philosophies. "Keep it simple stupid!" is one of the big ones, and even RTFM is lost on some software and online service providers that fail to even learn the software they are using.
It was poorly planned from the beginning, or planned by someone who had no idea what they were trying to do and padded a resume with things that they didn't understand to begin with making promises of things that could be done with no reasonable understanding of what it takes and timeframes of getting things done and publishing.
Planning is the biggest hurdle DDI has had because that is where it failed and why getting things to the PDF format is so hard because of poor planning and poor organization and optimization of resources human and otherwise.
There is really no excuse about poor planning. Just don't start until you are ready to finish.
So yes clicking print to PDF is easy, but so are the other things when everyone is working together and has a proper plan to get things done in advance, rather than piddle farting around to the last minute to get them done to cause things like Barbarian playtest to be pushed back a month, etc.
Example: Peter Lee should already have 3 articles about the new miniatures ready to go and photography of miniatures form the various new sets ready for preview so that when they are needed the editor and publishing team just grabs them to plug into the articles. If he does then he is one step ahead of the rest of the people, and if he doesn't then he probably wasn't allotted proper time to do so with all his other duties.
Diedre Moinen(WotC_DM, sorry I stink at French spellings) likewise could have articles ready for Visualizer for its potential release as well as the Dungeon Builder, and when they are ready for inclusion as an ad/preview for the Dragon, they can just be plugged in.
There is so much that could be done in advance that seems isn't is where the hold up and problems with DDI and the PDFs for it stem from. So stop waiting to the last minute and procrastinating on stuff you know needs to be done form whoever is deciding on the release schedule for issues/articles.
At this point the June issue of Dragon and Dungeon should already be planned what is going into them for 80% and some article assignments should have already been sent to people, and artwork assignments sent as well so they are not waiting until the last minute to say...did we mention we need that art next week that we never told you about yet?
(Although, in all honesty, I haven't had to do that since before .NET was around - and am quite happy about that even if programming for Oracle has improved over the years.) 
