How old do you think you should be before starting to administer GH or should it be used when gains from gear slow.

A friend of mine who is 20 has just started taking 4 IU ED, but after reasearching on this site and others would a 8 IU EOD or 12-15 IU every 3 days be more beneficial as his natural GH levels are high already and this better replicates in some way, the natural pulsing release form the pituatry gland doesn't it? Also wouldn't the EOD or ETD dosing strategy have less effect on his natural GH levels when he ends the cycle?

Thanx

T