Quickly can Gortat play pf next to Bynum?
The problem is going to be on the offensive end. Spacing is going to be very difficult. Teams will collapse onto A.Bynum and T.Evans and choke your offense.
In terms of defense and rebounding, a Gortat (PF) and A.Bynum (C) pairing would be immense ... just like Gortat and Dwight were but SVG couldn't put them together too often due to the problems they posed for his team offensively.