Observationally, the majority of bigger guys (220>) I see tend to do at least 2 exercises per bodypart.
There are also loads of guys with respectable physiques (<220) who say that 1 exercise per muscle is enough for max growth.
Hypothetical: identical twins, same diet and recuperation factors. Twin 1 uses 1 exercise per muscle twice per week, twin 2 uses 2 exercises per muscle twice per week. Both train to concentric failure in the same rep range. Who builds the most mass?
There are also loads of guys with respectable physiques (<220) who say that 1 exercise per muscle is enough for max growth.
Hypothetical: identical twins, same diet and recuperation factors. Twin 1 uses 1 exercise per muscle twice per week, twin 2 uses 2 exercises per muscle twice per week. Both train to concentric failure in the same rep range. Who builds the most mass?