it helps the ram get "up to speed". helps the vavle open. and you can take it out but its not the best idea. also if you go and by a new one from a hardware store that is a little heavyier you can lower you lpr pressure a bit
the extra spring pressure is actually very little guys... what you're talking about is around 90 psi for recocking pressure. If you're looking to quiet down the gun a bit and lower kick the way to do that is to replace your stock valve with a vapor or sonic valve.
The spring is there for a reason. To take down FSDO. That's why impy's have FSDO and Bushmasters do not.
another reason lowering the pressure of the lpr won't help you much is that the ram assembly is not the highest flow part around... you will experience inconsistency if you lower it below the rated specifications outlined by ICD...
But if you want to give it a shot, by all means... Just be sure you know what you're doing... With the spring the bushy can cycle at around 22cps... so yeah... lol
As for the argument about whether a lighter spring or heavier spring would allow you to lower the LPR pressure, the answer is simple. A heavier spring would allow you to lower the LPR pressure because the only time the ram needs a significant amount of force is when it is extending, because it has to hit the valve hard enough to release enough air. When the ram retracts, there is very little resistence, the only significant resistence is the spring in the ram, and that is very small compared to the force needed to pop open the valve.
As for "cocking", there's no cocking going on, the ram only extends and retracts. You could install a heavier spring, but it would probably be pointless. It would allow you to lower the LPR pressure but you would still have the same amount of force pushing on the hammer and bolt due to the heavier spring, otherwise your velocity would be lower. So, it wouldn't be any gentler on the paint.
you can run it without one if you want to deal with first shot drop off. I think the thick grease makes it stick a little too. I dont spring mine since it increases the load time that you can visibly see under certain conditions.
The spring is probably why people can run an angel at a certain rof on an angel with no problems but have chops when doing it on a bushmaster