Trying to play MCH with PUG's is pure agony.

[Valence]

What makes you think that a battleraise is more valueable than dismantle when you are already going for the clear? Dismantle always has value while a battleraise doesnt. The moment both healers die its pretty much over anyway. I dont play casters that much but im pretty sure that the priority when it comes to who has to raise always falls on the healer. A RDM most of the times cant raise without breaking his long ass combo since the 2Min burst lines up with mechanics where ppl tempt to die a lot. A SMN doesnt have swift for like 70% of the time if they play optimally to snapshot slipstream. It hurts your party more to bring a RDM/SMN than a MCH would when it comes to the overall party DPS to meet the dpschecks.

That being said since you took m5s 50% as an example on the quote after this. MCH actually seems quite solid surpassing DNC BRD and SMN in rDPS and DNC,BRD;SMN,RDM,PCT in aDPS. rDPS isnt everything, aDPS matters aswell. DRK as an example is most often the lowest rDPS tank but still considered the best tank when it comes to overall partyDPS and Killtime because of his synergy with raidbuffs. MCH in m5s for example could technically start of with a Drill -1-2-3 to line up all high hitting GCD's and Wildfire with Raidbuffs for even more aDPS since you wont lose a usage of Airanchor, Chainsaw, Wildfire, Queen ect with current killtimes.

It's an old debate without a clear cut answer.
Raises are great for progression, but tend to become less appreciated once a group is through, although it's still a safeguard when both healers die outside of a bodycheck mechanic.
Dismantle is great on paper, but in a sea of mitigators, your 10% has a tendency to turn into a 5-7% once stacked. Which is still appreciable, but it's not exactly something to fall over either. It used to have a lot more value back in the days when a lot of mitigators (notably tanks) actually targeted STR/DEX/INT/MND instead of flat % numbers, and there was overall less of them floating all over.