The close LSA typicly will give a higer peak HP/Torq #s, a wider LSA will typicly give a better average HP/Torq #s.
Close; a tighter LSA increases the communication between the intake and exhaust tracts, accentuating both the beneficial (better scavenging) and bad (idle). Typically tightening up the LSA concentrates the power around the torque peak because the torque peak is usually where the better scavenging occurs. That increases the peak torque reading but usually costs a few hp on the top end.
A wider LSA spreads the power out, making the peak torque lower but boosting the top end a bit. This works well in a street engine that is capable of higher rpm; an LS engine for example.
As you said, there are a lot of compromises to be made in cam selection but I tend toward a tighter LSA on both the street(110-112) and the race engines I build (road course and oval - as low as 102).
