I see the search function is invisible again.
Serious question, since many of you seem to have experience - what if you manually pulse the beams? Do they then behave like pulse lasers in the heat & power department? I'm thinking it would be analogous to different automatic weapons in FPS - if you shoot in short bursts, your accuracy is much better, but boy is it handy to be able to fire a constant stream of bullets when you need to.
I don't know how the timing mechanics for sustained weapons work in ED (well weapon as singular, mining lasers aside) but in any case the beam has distributor draw and thermal load stats which are way worse than on the pulse. So assuming you lose no damage by pulsing what is intended to be a sustained weapon, you would have DPS that scales to how fast you pulse it but will likely be no better than pulse if it can even compete, and the heat generation/distributor draw would still be less efficient. The reason you put the beam on in the first place is throw efficiency out the window for a relatively small edge on DPS.
It's like buying an original land rover and comparing it to the fuel efficiency of a smart car; yes you can reduce the fuel consumption by driving it less or in small bursts, but to make it the same distance, you're still doing it at a far lower efficiency.
Wouldn't recommend it but then again, experimenting and failing is more noble than theorycrafting.