Im stumped on something:

In the past I had a trial and error run. (December 2011) I bulked to 235lb in hopes of new strength and size. I got both. I wanted to cut to about 220lb for college ball, especially since I was changing positions. I started cutting (March 2012) and in a heartbeat, I dropped to 205lb and lost muscle strength, and minimal bodyfat. It was a nightmare.

Fast forward:

I have since learned a lot, now staying at 215-220lb and getting stronger, faster and conditioned with football training at my new college. (Transferred this past january from a D-1 school.)

I want to learn more about the cutting topic for my general interest, however.

When someone cuts, do they lose muscle from the calorie deficit or lack of protein intake? If a person at 235lb, shooting for 220lb with minimal/all fat loss for those 15lb in mind, can they keep their protein intake at 220 grams a day and not worry to much with calorie counting (within reason), so long as they know they are getting that protein?