The answer to "why" was in the patch notes...to make all LPLs the same something or other compared to other pulse lasers. The trouble is that it wasn't a good reason.
SPLs, as a point of comparison, are ok to be hotter since they're still not nearly hot enough to impact DPS due to overheating, and .5 ton heavier than the SL isn't drastically affecting the mech using SPLs either. Further, their shorter pulse is actually useful for scout mechs (where SPLs are used) since 2 mechs fighting at a combined 300 KPH see value in that little bit of extra accuracy.
When we look at LPLs however, they're much hotter relative to LL and their greater burst damage doesn't compensate sufficiently to offset the heat which is important in a brawler type weapon. Also, the extra 2 tons of weight per LPL (instead of the mere extra .5 tons of the SPL) makes a significant difference in the build's overall efficiency particularly when that extra tonnage could go to more DHS to help compensate for what is already an overwhelmingly hot weapon system. Meanwhile the shorter pulse time of the LPL is pretty meaningless on the heavier mechs that typically use it as fighting at the speeds of heavy and assault mechs and being unable to put all the damage where you want it is a sign of Parkinsons and you should make an appointment to see your doctor if you recognize this important symptom.
So, making all pulse lasers follow the same kind of upward curve in performance doesn't really work in the real game. That's OCD thinking not game balance thinking.
The symmetry the devs sought has worked out nicely in one respect however...
SPLs: good
MPLs: marginal
LPLs: crap
Edited by Huntsman, 12 July 2013 - 06:47 PM.