Pulse Lasers as described in Battletech are more like laser gatling/machineguns. They exchange a higher rate of damage with higher heat, cost, weight, and reduced range.
I've not understood the reducing of pulse laser damage, because it flies in the face of hard rules.
"The pulse laser uses a rapid-cycling, high-energy pulse to generate multiple laser beams, creating an effect comparable to machine-gun fire. This design improves the hit probability of laser attacks and causes more damage per hit, though at a cost of increased heat and slightly reduced range. Treat pulse lasers the same as standard lasers, but apply a -2 modifier to the base to-hit number" -Battletech Master Rules (1998, FASA. The wording is the same on my oold Star League 2750 TRO from 89 though)
Basically, a pulse laser does more damage per hit, and it hits much more than a beam laser, because the pulse laser doesn't need to linger on the target for the 10 second combat "turn" that a beam laser does.
Back then, a Clan Large Pulse Laser did the same damage as a heavy large laser or ER large laser, with better range than a Heavy laser, weighed 2 tons more, created 8 less heat, and had better range, AND had a -2 modifier to hit. (Negates negative effects of moderate movement, almost negates JJ-caused innacuracy, negates moderate weather/time of day effects, etc)
IS pulse lasers did 1 more damage than an ER or large laser, same heat, and had a better chance to hit, at the cost of reduced range.