Bodybuilding and fitness quickly stops being a 'solitary sport' with the introduction of a steady training partner. Almost immediately, both lifters (or however many are involved in the team) will arrive at the metaphorical table, with routines, diets, and philosophies in hand -- both hands! A certain degree of diplomacy is employed, then comes the pro/con debate, and finally the team is forged with an unspoken compromise on all matters discussed. All of this can happen over the course of five minutes, or it can be an ongoing process that spans the life of the association. But the bottom line is quite clearly drawn in the sand -- you've got more than one person out to build a better physique -- and it's going to take the collective will and effort to get there.
When looking for a workout partner it's almost imperative that you find someone you get along with, but who's also going to have your back (and you his). Few people are consistently committed to training, eating clean, and bouncing back from life's many pies in the face without resorting to over-eating, not training, and feeling sorry for themselves -- I know it all too well -- these are some of my chief exit strategies of past, but my bodybuilding groups keep me focused! You want to find a workout partner that's going to keep you focused, but you also need to be ready to keep him/her focused when the time calls for it. Because even when we train in bigger groups, the bond between primary workout partners remains almost distinct from everything else. You can be like the mainstream that just doesn't get it -- or you can overthink things in the gym like I do. But what's pretty clear is that you and your work partner(s) will develop a very unique bond that will transcend gym hours and gym walls :)
Look Carefully. Choose Wisely. Train Hard, and have fun! :)