This is some people looking over difficult to read/unclear rules and making the best ruling possible to keep weapon options other than double weapons open to the tempest fighter.
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.
The FAQ answer does put additional evidence against the first rules interpretation I posted (which I've already discovered makes no sense because of the defensive keyword), but does nothing to discredit my second interpretation.
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.
It's not a huge deal one way or the other, I simply have more fun playing games balanced with lots of options.
Some people prefer clear cut option one is better than option two game mechanics. That's fine too, but it's not my cup of tea.
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.
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.
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."
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.