that is the recommended diet to gain size and muscle mass. i would try not to exceed it.. and work your way up to it, dont just do a full diet switch in a matter of days esle expect significant fat gain.
the carb counts on this site have also been know to be a little high, so you could drop them a bit if you feel you need them.. i wouldnt go below 2g per lb of bodyweight if you are looking to gain.. maybe even 2.5 or 3. all depends on the person..