So I was mass killing some mandies today for some people. And one person made a comment that I didn't need to pull so many because I was killing them at the same time and you can only get exp from 10 mobs at a time form a simultaneous kill. I didn't think this was true at all, but we tried it and I pulled 20 mandies 1 shotted them all, and exp was only received that amounted to 10 deaths.
I ended up pulling 10, weakening them with thermal pulse, then pulling another 10. Use a charged whisker without ascetics so that it wouldn't 1 hit all of them but kill the weak ones, and then finish the rest with a whirl. Exp rate basically doubled/pull after doing this.
Was this common knowledge or is something glitching?