If you take too much you can have a heart attack (as i once very nearly did - to my dismay) - so in one respect, no more isn't awesome.
I was under the impression that the doses you described were the regular protocols, and not high doses - as 16mg/day is the lower end of the dosing protocols common online.
AFAIK, one starts with just 4-8mg a day and just like clen, they increase the dosage on a daily basis to assess tolerance to the drugs side effects - when this level is reached one backs off a little and sticks with that dose for the duration of use.
It isn't wise to jump straight in at a max (PED) dose with beta-2-symphatomimetic drugs and as such, it is totally dependant on the individual as to the effectiveness (or more accurately ability to tolerate sides) of the higher doses rather than purely their choice to do so.
But generally speaking i would say yes, if you can handle the clear increase in side effects then i would expect the benefits to be increased too.