No, the rules are clear. They just don't say what some people want them to. A ruling is based on what the rules say, not what you want them to say. You're twisting bits and pieces of the rules into a different rule that gives you the answer you want. That isn't a ruling, it is a house rule.
If the rules are clear, why do so many people ask for clarification? I've sited
my sources and my reasons for my interpretation, the FAQ quote you sited in no way diverges from my second interpretation. Treating double weapons as single weapons in no way makes both ends off hand. In fact it supports my interpretation because the double sword is treated as
two single weapons, meaning that each weapon can have different properties.
Your second interpretation isn't an interpretation. it is something you fabricated. You created a split where none exists, in either the description of the double sword in the text or in the table. WOTC_Logan has already made two posts, one in which he explained that the orginal writeup had two seperate lines and one in which he said he couldn't speak to the reasonthat it was changed, but that it was a moot point with regard to the "final double sword" which he only used as an example. It changed, and the description clearly describes it as two identical longsword blades, not a longsword blade an a rapier blade. However you dress it up, your "interpretation" isn't a ruling or interpretation, it is a house rule.
Would you mind posting a link to the WOTC_logan thread. I've lost track of it. Thanks.
Fabrication
Fab`ri*ca"tion\, n. [L. fabricatio; cf. F. fabrication.]1. The act of fabricating, framing, or constructing; construction; manufacture; as, the fabrication of a bridge, a church, or a government.
That's an odd thing to say about someone, but it's clearly a false statement. There's no way I could do anything of those things on a forum . . . so you must be lying. Dun dun dun!
Sorry, I really couldn't resist. Anyway so here's a few facts you may not have noticed, at least I hope you haven't cause then I'll have written them twice for no good reason and I
hate wasting effort!
- Flavor text =\= rules text.
- The light blade and heavy blade being separate isn't part of my interpretation, it was a side-note. (though because of how useless it makes the rapier I'd likely house rule it into a heavy blade only)
- The point was different sides can have different properties (the Urgrosh is only half / axe half spear) [but all man]
- In the explanation of double weapons it specifically names one side as the off hand side, and the other as the main hand side.
- Therefore: only one side has the offhand property!
This is wholly irrelevant when posting about what a rule is. A rule says what it says, regardless of whether you like it. Again, if you're twisting a rule to make it say something other than what it actually says, you've moved past making a ruling and into making a house rule.
I think I've already answered this. Next!
As an aside, I don't like double weapons at all, any of them, period. I do like options though, I just like them to be meaningful and different. Which means that some options will be better in some combinations than others. A bastard sword isn't as good for a tempest fighter as a double sword. That doesn't mean the double sword (or double weapon property) is overpowered. Just like it didn't mean that the bastard sword (or the versatile property) was overpowered because it is a better choice for most swordmages than a double sword. There are options which make the double sword nice for the swordmage and options where weapons other than the double sword or whatever are nice for the tempest. Those options aren't always as simplistic as using a different weapon and getting the same level of results. Sometimes you need to mix feats, races, magic items, paragon paths and/or multiclassing to get the benefit of a switch. I prefer complex options to simple options. And, if you have good and viable combinations, and make the good combinations only viable by making a component worse, combinations using that component that were previously viable become non-viable. You reduce the number of viable options, and the number of options overall. So trying to give yourself some false moral high ground by implying that you have desire for a superior game with more options is disingenuous at best.
I enjoy that you started that paragraph by pointing out an option you don't like, shows you have multiple dimensions, you're conflicted, an interesting character. Anyway I mostly agree with you here

I just think there are more "good and viable" options for tempest fighters than double weapons.
Also I don't think that word means what you think it means. You might want to get that checked.
On churn: Posting "I don't like this rule and I think it should be like this." is one thing. It is honest, and generates debate. Posting "This rule I don't like actually says this." when it clearly doesn't, and twisting bits of text selectively to make a point generates confusion and churn. Most particularly, the irrational calls for aditional clarification when none is needed. There are things that need attention more than multiple FAQ entries and rules updates to confirm that they mean what they say. What's the update for Double Weapons going to say? "Wielding a double weapon is like wielding a weapon in each hand, really, we mean it, for sure."
Well I think it'd be cool if anyone but halflings had any reason to use the rapier. Also a solid statement of "while wielding a double weapon only the end held by your offhand has the offhand property" would probably help clear things up up the rule with skeptics.
What would I possibly accomplish by trying to confuse people about the rules. I'm giving people a reasonable interpretation that keeps double weapons from being the end all Tempest weapon that many seem to think it is. Also I don't see anyone on this forum churning . . . at least I don't think I do. What are the symptoms? Nausea? I hope it's not nausea. I have a tender stomach. Does anyone else need some Pepto Bismol? I'll make the run!
On the FAQ: Does someone have some "official" statement making the FAQ unofficial or that it is just a customer service answer. The only WotC information I've seen on the process is a customer service response to a question which said there wasn't an official answer, and the CS rep said he would send the question back to the developers of the game and that "hopefully" an FAQ or update would be forthcoming. I've never seen anything that said FAQ updates were made without the input of the developers,
But, really the 'FAQ isn't official' line is no different than what will happen if an update is released. The same people complaining that the existing rules are unclear because they clearly state something other than what they want them to will continue to claim that the updated rules are unclear if they don't like the updated rules.
Again, the FAQ response supports my interpretation. Other than that I'm not really sure.
Maybe if the rules are clear people will just be like "oh that's lame, lets do this instead," maybe they'll keep complaining until they pollute the ozone layer so badly the sun burns us all up in a supernova (yes, supernovas and ozone layer decay are related. What did they teach you in school?), or maybe they'll be so disingenuous they'll convince us all that they're right and dragons will erupt from the Earth then chaos will ensue . . . CHAOS!!!
( I don't like being called a liar for presenting my ideas. I'm genuinely sorry if you felt insulted by anything I said before or during this post. I tend to respond sarcastically when confronted by people who use the same argument repeatedly without giving evidence that my interpretation is wrong)