Quoted:
ok lets try this....
is cutting a half coil off the buffer spring a horrible idea?
I'll take a shot at specifically answering your question and not make assumptions on your lever or other pieces, seriously look there first, too easy no to try. I cannot directly answer your question with respect to your application but in theory I would say no problem. This is the procedure that is recommended on a number of the flat coil spring applications. When using the Tubbs buffer spring (decent flat spring), they sell only one length spring for both the rifle and the carbine. If issues are detected with the carbine they suggest cutting 3 coils to begin with and 1 coil there after until the firearm cycles properly. Springs are cheap and I can see no harm in doing this.
I have one DI carbine that sports a Young's National Match M16 BCG, a Spikes ST-T2 Buffer and a Tubbs spring. Think both stiffer spring and more mass when cycling. This rifle was fine with a regular spring but just for giggles I wanted to see just how little recoil I could make this gun have. Once the spring was installed I ran into the failure to lock back situation. I half way expected this outcome and of course I knew what the problem was but wanted to see if shortening the spring was acceptable. I called Superior Shooting and spoke with one of their technical people to obtain this information. I haven't seen it in print. For what it's worth this gun is an incredibly smooth carbine (no FTF or FTE and locks back every time regardless of ammo). You no doubt have heard this claim before but when it comes to recoil in all seriousness it isn't much different than a .22 LR. Much less perceived recoil than an off the rack AR. Take my words for exactly what they are worth, just another opinion.