Absolutely not. If you check @Flawless ’ penance feedback thread you can see there are far far worse offenders that are grindy beyond measure, especially a few Ogryn ones:
BoF is pretty much in the middle. Now if you tried to argue the same thing about the Loner backstab penance I’d agree. That one is slightly too long. Or the Veteran focus fire penance, but BoF? Nah.