I think you have to think about it like this. In European soccer, the sport is very much a case of the haves and the have nots. When you talk about the best soccer in the world being played in Europe, I think that you are correct, but only for the teams that are at the top of their leagues. Once you look at the teams at the bottom half of the EPL, you will see that the style and quality of the game isn't absurdly beyond that of the game in the US.
You can call it 'Double-A' ball all you want (and no matter how much you say you love double-A ball, it really sounds like a backhanded compliment), but if you had ever watched a game at the bottom of the EPL, then I don't think you'd really think that there is an absurd difference between the two leagues. When you get even lower like the British Championship/second division (Triple-A ball?), you'd have a hard time arguing that there is a ton of difference between the game and the MLS.
If you wanted to say that there is an absurd gap between BM/RM/Barca/MCFC/etc and the MLS, then yeah, you'd be absolutely correct, but in the last 3-5 years, the MLS has really increased the quality of its play. They have recently started opening up development academies to emulate the European game, which is only gonna continue to increase the quality.
But in your analogy, I'd probably compare the quality of the MLS to the bottom of the EPL (in good years) through the top 2/3s of the British Championship. There are some teams that can be argued as outliers (personally, I think the 2010 LA Galaxy team was awesome, and the Earthquakes this year are Barkley-style turribull, especially after watching them vs. Chivas this week). I'd guess most teams probably sit between the top half of the Championship and right below the 3 or 4 teams fighting for promotion.
Obviously you can't truly compare the teams without them playing, there are a lot of fans that are truly MLS fan-boys that think most teams would be lower half of the EPL quality, and there are European purists that think the MLS is closer to "single-A" ball than the EPL, but that's my opinion and I feel like I've watched enough of the game to have at least a pretty informed opinion on the matter.