I think overall, Romo is a better QB than Alex Smith, but I think Alex Smith is being used far better in KC than Romo is being used in Dallas. Also, Alex Smith isn't burdened with having to carry the load because his defense can't hold a lead or get a key stop.
There's also a committment to the run. Jamaal Charles (4.3yd/carry) is NOT Adrian Peterson. He's got 177 more yards on 59 more carries than Demarco Murray (4.9yd/carry). But KC is committed to running the ball enough to help the offense. It helps that they can get leads and have a defense that can hold leads.
Dallas has more weapons than KC. They have Bowe, we have Dez. They have Avery, we have Austin/TWill. They have ?Fasano?, we have Witten. They have invested in Oline. KC is better coached and they have better front office staff, player development, scouting, etc.
The difference is that in Dallas, Andy Reid would have had to deal with Jerry's meddling. There, it looks like he's got the freedom to make it his team. When Reid came in, he held over just three coaches from Crennel's staff. LBs coach, DBs coach and the assistant Strength & Conditioning coach. He would not have had the luxury in Dallas. Jerry would have hired a staff for him.
it's night and day. The coaching talent Reid brings to a team would have been wasted in Dallas.