Not necessarily...the Giants had the highest powered offense in the NFC East...with Barber, Toomer, Burress, and Shockey as major threats. They also have 2 All Pro defensive linemen...yet they were pushed around at home in the playoffs. This is a game thats won/lost in the trenches and I think morale and attitude have much to do with who wins and loses those battles on a week to week basis.
Talent isn't always enough to win football games, especially in this day and age when the difference in actual outcome between a 1st and 3rd round pick can be pretty minute.
Look at two of your lifetime Cowboys on the offensive line that won you championships ...Newton (played in USFL before NFL, undrafted) and Tuinei (wasn't even an offensive lineman his first few years in the NFL, but became All Pro, yet was also undrafted). Bill Bates as well (undrafted), not the most talented guy but played hard and was a fierce and tough competitor.
I think alot of improving from college to NFL has to do with heart and desire...many players who were written off have come and become All Pros in the NFL. Desire can take a player to a whole new level.