Oh, definitely.
I guess that would be determined by the ceiling of protein synthesis and different people will have higher or lower set points. Optimal nutrition and protein amounts will ensure that protein synthesis is maintained at it's upper most level (ceteris paribus
) and I reckon that no amount of stimulus and/or caloric/protein intake above a certain amount will increase protein synthesis past a certain limit. But each person is different. The only way to really increase it is...you guessed it...gear.
But it's a bad idea to try to plan training by the appearance or lack of growth, if that is what you're getting at, at least for the average natural trainee. Growth is slow and nebulous.