How much protein can your body absorb on/off cycle

[Schwarz]

I could be wrong but think it also depends on the weight of the person.
Even when maintaining your muscle you need 1.5g of protein per pound bodyweight so it stands to reason that a bigger person would need more to maintain and more again to add mass.

Well that's my point exactly. So how can someone possibly regulate themselves to 30g of protein per serving!