You cannot compare 50HMFPs and 55HMFPs. in 50HMFPs there is a LOT you can skip just by moving carefully; in BoI you can even skip most of the bosses. That was one of the major complaints about the 50HMFPs.
I have quite literally run all the 55HMFP at least 25 times and in those 100+ runs I can count on one hand the number of times a group was left significantly short on the number of kills needed to do the bonus boss (10 or more).
You've got ten fingers on one hand? MUTANT!!!
Seriously, I don't need the bonus on at least my top 4 alts any more but if 1 person does then I'm happy to do it. It's not like they present a challenge or lead to wipes any more (like they did just after ROTHC release)