Warbucks.
First off, carrying has a pretty big effect on breaking tackles because bort is crazy and made it so. Simply how it is, nothing to argue about here.
For the # or WR's arguement, personally I beleive any owner who has a number of WR's different than 4 is doing their players/team a dis-service, though I suppose I could almost understand 5 WR's on a team. All teams should have about the same number of WR's, so it should be a mute point at any rate.
I sound like a know-it-all on specific subjects because I beleive I tend to have a good amount of knowledge on the subject. I have a proven track record with the WR's on my team, as well as a complete crapload of keen observation of builds throughout recruiting/trade block/and build forums. I do not, however, walk around telling people possibly incorrect things for which I have no evidence simply because I think I am smart, which is what some people tend to do... If this makes me come off as an arrogant know-it-all, then so be it I suppose.

My own WR chad hill got 143 catches and 1646 yards last year on an offense that passed 55% of their plays in season 3. He is currently averaging 8.5 receptions and 91 yards per game on an offense that is passing 60.8% of the time. Last season we ran for over 2400 yards. This season we are on pace to rush for over 2700 yards. To assume every productive WR in this game is on a team that passes 80%+, or even 70%+ is just plain incorrect...
The biggest factor in getting good stats is being part of a successful offense that keeps the ball moving, regardless of via air or ground, since that leads to more opportunities for the player. A successful offense can be had with a good gameplan and good builds. These good builds, directly translate into having a successful offense that can keep drives alive. Good builds both directly and indirectly lead to good stats in general my friend. If you take some guy who's a #1 WR averaging 3 catches a game, and you bump his offense to 80% passing, he might get 4 catches/game. He will not suddenly transform into Jerry Rice...
No stat, neither ypc or catches/game will tell you everything about a WR. Catches IMO is a more telling stat though as long as you take into account the players previous team situation and spot on the depth chart. For instance on my team our #4 WR has 10 catches in 6 games, but he also does return duties and is in a role where he doesn't get quite as many plays out there at WR (not to mention having to compete with a ton of other weapons for our QB's attention). I have no doubt though if he was higher on the depth chart on another team he'd be studding it up, based solely on his build.
^why I sound like a know-it-all....
