Try that against a boss.
I repeat for a 4th time
This is a density destroyer, not a boss hunter.
But still, here is for you the avg time required to kill each boss if merc attacks alone :
andy - 0.87s
duriel - 1.53s
meph - 0.95s
diablo - 2.68s
baal - 4.76s
Maxroll does include in its calc all the factors. Hit chance, %crit, %cb
Yes, you could optimize that kill time by like a tenth of second vs bosses, with a build made exclusively to fight bosses on high payer count.
You'd lose a lot of everything else just to accomplish something that the build is not made to be good at.
Just play something else if you can't understand that.