My opinion on this subject is if size is your ultimate goal, then getting as strong as you possibly can for a moderate rep max is the most efficient and guaranteed way to get bigger.
If someone can Front Squat 1.5x their bodyweight for 8-12 reps, then they are going to have some extremely well developed quads, no question about that. Same goes for other body parts, if you can do chin ups and dips with 2 plates hanging around your waist for 10 reps your gonna have size on your arms.
Another thing I believe in is that your strength in any given lift is basically a skill, if you want to get better/stronger, you do it more. This is why I'm a firm believer in volume, for example if you are doing 60 total reps of bench 2x a week, that's 120 reps a week. That is plenty of work/practice to get stronger and grow off of.
So basically an ideal routine for me would be one that - your goal is to get strong in a moderate rep range, plenty of volume, and one that includes a decent amount of variety in exercise selection, since this is fairly important for bodybuilders.
Frequency, Exercise selection are other factors as well but those are pretty simple for bodybuilding routines.