Okay, since there are so many people on here who don't understand NFL "caponomics", let me clear this all up for y'all.
1) All 32 teams were notified in writing that 2010 salary cap dumps were not going to be allowed.
2) 2010 being an uncapped year is essentially meaningless in this discussion. There was no salary cap limit for that year, however there were strict instructions given to all 32 teams that they were not permitted to "dump" salary into an uncapped year to remove future cap obligations.
3) "Dumping" cap, as referenced above, essentially amounted to cheating the system. You could re-sign a player to a $40 million contract over 4 years and pay him $37 million in 2010 and $1 million each of the next 3 years. This is what the Skins essentially did with Hall and Haynesworth and the Cowboys did with Austin. They dumped their salaries in 2010, despite explicit instructions not to from the league office, in order to free up more space for 2011-beyond.
4) Had all 32 teams ignored the memo and dumped salary galore, this would be a non issue. However, 28 teams followed the rules. 2 teams (NO and Oak) tiptoed the line between following it and not following it and were given a slap on the wrist. The Cowboys and Redskins blatantly ignored the league mandate in order to get an unfair advantage over their competition (how'd that work out for them?).
5) The Cowboys and Redskins were given six notifications from the league office that what they were doing violated the league directive and still opted to proceed.
6) The league office's approval of every deal is irrelevant. Contract restructures happen all the time and I've never heard of the league not allowing one of them. They couldn't say "no, Dallas you can't pay Miles Austin that way". It's Dallas' right to pay players how they see fit. However, the league most certainly can take them to task over ignoring a mandate that everyone else followed.
7) I've heard Cowboy and Redskin fans say this is lesser-valued owners getting back at the two richest owners in the game. That's @#$%. They are getting back at the owners who attempted to break the rules and cheat the system. Had Carolina and Arizona done the same thing with Larry Fitzgerald and DeAngelo Williams, I'm sure they would have complained as well. The fact that this action is going against Jones and Dan Snyder is purely coincidental. Actually, it's not, because they are the two NFL owners arrogant enough to think they could break the rules and not be held accountable for that.
8) The NFL had the "30% rule in place" before the 2010 free agency period even started. So this is not some retroactive penalty that gets forced at the commissioner's whim. This is a rule that a lot of football "capologists" knew they were breaking for years, even before the 2010 uncapped free agency period wrapped up.
9) What really gets me is that certain Dallas and Washington fans actually think that they are being penalized for being shrewd. They think that the Dallas and Washington front offices were the only ones who discovered this loophole and now other teams are retaliating out of jealousy. That cracks me up. The Redskins have, over the last 15 years, had arguably the worst front office in pro football (besides Cincinnati perhaps) and yet their fanbase is giving them credit for discovering this stellar, super-stealthy way of tricking the other teams to wipe away salary cap. Really? There are front offices in New England, Baltimore, and Pittsburgh which due a fantastic job every year. Did you really think that your genius front office in Dallas and Washington discovered this loophole while the 28 other front offices, many of who are infinitely more competent, missed it?