I guess I'm one of those MCH that hasn't noticed a problem? I don't parse, and I'm only 57, but I've been running with a pretty set group, with SMN as the other dps, and while my AOE is pretty terrible compared to hers, I think I'm doing well on bosses. On a boss, I play my rotation this way:

Hot Shot -> Blood for Blood and Hawk's Eye -> Lead Shot -> Raging Strikes -> Reload -> Wildfire -> Split Shot -> Slug Shot -> Reassemble -> Rapid Fire -> Clean Shot -> Split Shot -> Slug Shot -> Clean Shot

I weave Gauss Round in as I can, usually starting just after I start my initial round of Shots. I tend to save Quick Reload until I get a natural proc from Split Shot (so that I can get a guaranteed 200 potency Clean Shot) but I've been wondering if it wouldn't be better to change that up. RNG can sometimes not be on my side, but again, I've been able to keep up with our SMN without trouble.

I do miss Second Wind though, so I definitely agree that MCH needs a self heal.