Altruismo:
You forget about stamina issues , so unless you have a superb stamina amulet (I don't), I wear a 15% SCD, you'll compete stamina for HoV vs Nuke, so you'll actually lose nukes if you go the HoV route. BB is only 10 stamina, which recharges by the time it is finished casting and I position myself for the nuke. HoV at 35 stamina will prevent a nuke. Additionally if you need to actually block anything, HoV further slows down the nukes. As such I cannot recommend HoV unless you have a superb stamina amulet.
HOV for 35 stamina every 13-18 seconds is a stamina concern, but a combo for 90 stamina every 10 seconds isn't... got it 
I didn't forget about stamina issues, I assumed you were talking from the standpoint of having the Stamina amulet since, you know... combo combo combo. While Shield blocking too is it?
You still assume the 35% damage translates to direct multiplicative damage for the party, and 3%% less time to kill. It does not, as it is additive to the other bonus damage multipliers (which do multiply with other things). Also, do you not understand what overkill is? A footsoldier has about 3.5k health. The reaver does about 2k damage per dragon rage hit before fervor, taking two slices to kill the footsoldier. Added 33% damage to that ideally would mean 2.6k damage per hit... but that still takes two hits to kill the footsoldier, as the first hit takes the footsoldier down to sub 1k hp, then the second finishes them. Anyone with a lot of burst damage is in a similar situation.
That's a really high "raw" Dragon Rage hit, yet an ironic choice of number for your argument.
Can you tell me how many hits that same Reaver takes to kill a footsoldier with a non-Fervor crit? Now with HoV?
Howabout non-crits, Rampage + Fervor? Now add HoV.
Notice anything?
I'll save you some time, it's 2 hits, then 1 with HoV in each case.
Please be aware, I'm not trying to prove my point with your numbers, I just thought it was an amusing choice for an example.
Regardless, the damage is also not wasted on the mobs with more health than the standard grunts (Brutes, Pride, Rage, Commanders etc.), the Reaver in your example gains a lower "percentage" boost to total damage because they can self buff so much, but HoV is still a raw 700 damage increase (your numbers) per swing. And it makes a significant difference to ranged attackers with low/few damage boosts or those with multiplicative (flanking) damage boosts picking off wraiths, etc.
And what are you hitting for cool-down reduction if your team is over-killing so much? 
Obviously because
A. You haven't been in my games
B. You haven't tried it yourself multiple times
C. You don't have enough experience and perspective.
I cannot guarantee the first, but the second and third are up to you to try out.
"You're wrong because I play more", or something... that's not actually a counter to anything other than me claiming I'm more experienced than you, which I'm not.
I mean, sure you've promoted way more times than I have, but this game isn't exactly rocket science or high speed twitch, it's not even unpredictable. Assuming other people are simply "not good enough" at the game isn't a useful way to exchange information.
I got Caliban really early, and as a result I play Templar (and Lego) a lot and really enjoy both classes, I also like to try many different builds, even deliberately "inefficient" ones sometimes looking for funky synergies.
But to address the ad hominem you seem to be levelling at me: Yeah, brah, I know how to play.
The only time I've gotten a noticeable benefit from BB/Combo cool-down is when I'm soloing Threatening, because with other agro and damage sources present in a team in Perilous, I always found that BB/Combo builds "catch 22" themselves:
The combo does so much damage that I'm either left with near-dead/few targets for BB cool-down reduction that are dead before I can combo anyway, or I'm left with no/scattered targets to get cool-down reduction on, making the cool-down reduction minimal to non-existent and a faster combo ineffective anyway.
I get how your build can increase how often you combo (if you have targets inside the circle). But you've comboed, you've cast BB, throw Shield Wall and only 100 starting stamina into the mix and you're waiting around for the stamina to do a second combo anyway. I don't see why the cool-down reduction is so vital to you unless your team is dealing really sub-par damage, in which case.. HoV.
Like most of your builds it seems to revolve around the idea that you, personally, are doing everything. And while that is a criticism, I don't mean it to suggest that your builds are bad.
I also know you know how to play DAMP, but seriously, which is it? Your team does so much damage that HoV is overkill, or your team does so little that you have plenty of targets to auto-attack inside your BB circle for cool-down reduction? They are kind of mutually exclusive scenarios.
If you've actually been talking about soloing the whole time, then saying that in the first place would have answered my original question.
I think teams clear faster with HoV, you don't, it's cool.