Ok guys, I just logged of PTR testing.
At about 185k DPS, CoB timing for Ghom MP10 is 1m14s. I was quite surprised that vampiric bats and plague bats were "useless", since Nubtro's research shows that plague bats should be returning higher damage after the 5 sec stabilization.
Skills that do not interrupt the channel: SW, SH, Horrify.
Skills that stop the channel: BBV, SB, ZC, Haunt. (didn't try the rest)
One good thing about this patch is the buff to pets indirectly. For example, I cast Horrify (100% armor), then summoned my 3 super dogs, with the Fierce Loyalty and Blood Ritual passive. Due to the added armor and regen, none of the 3 dogs died while tanking Ghom MP10! This means, after Blizzard fixes the thorns damage in a future patch, pets can very well be a viable build. By extension to this findings, players who prefer BM, JF, Zombie Handler, can all find their niche build to support their pets.
As in previous patches, I was disappointed by the Fetish passive. Seems that none of them proc'ed, or they died the instant they proc'ed because I did not see any running around. Did someone mention that FS procs very well with bats?
In another test, I used a total gear of 1288 LoH without LS. Died miserably to Ghom (face tanking without running around). Terrible proc rate for CoB.
If this PTR goes to the live server, CoB can provide alternative DPS, but as written in the Blue post, it's meant to be played in co-operative mode where someone else is doing the tanking. It also does not solve the problem of needing to avoid the frost and ground effects.
My view is that the bats are much better than previous patches, but still get an overall fail in terms of design concept. So ironic that WDs need to get in melee range for the main skills that can work -- SH, Bears, CoB, and in the case of CoB we still need to maintain that channel without moving. Best part of the irony is Monks get to TR while channeling, and Barbs get to move around the map while doing damage (both melee class), and WDs must hold ground and control the bats! LOL to Blizzard design team. I wonder if they really know their game.
At best, this alternative is meant for Ubers only, and not really for going around the Acts.