I just re-read my response and realized it's a little disjointed (at best).
The main point I was trying to make is that you can get stronger through other means besides mass gain. Although, heavy weights provides a nice growth stimulus, and excess calories will fit in nicely with that stimulus.
Like Steven said, keeping cals. in check will keep mass in check. The laws of thermodynamics still apply to humans.
And if you don't think kettleball squat cleans are difficult, I say, step up to the med-ball
- CJ Kim