I doubt it truely broke a character to the point it's not playable but I can see how some would feel the nerf to it made their character less enjoyable to play. Now you cannot deny that. Across the borad on the nerf human characters lost 5 passive skill points to every skill... they no longer jumped, tumbled, hid, DD'd... or Umd'd as well passively.
On another note...
1.) A 20 second boost is hardly worth the AP spent. In the new coming update to it HV is still very weak in comparison to other racial enhancement lines. Ie.) a 20 second +5 ac boost 5 x rest is nothing compared to dwarven armour mastery III (+3 AC all the time) likewise a +5 20 second damage boost x5 is nothing compared to +2 passive axe or longsword damage. Take Madstone crator on elite and tell me how effective 5 20 second boosts would be in there between shrines then compare that to an elven attack II or dwarven damage II effectiveness. If you can tell me that madstone requires a total of 1 min and 40 seconds of actual mob encounter between shrines I'd agree but I bet my best guess isthe average madstone run takes a total of 20 minutes. Puls should you do speed runs nobody will care to wait for you to recharge or wait for your cooldowns...
2.) What's more a boost has a cooldown... there is a manditory 10 sec? between each boost... also within the first 2 seconds of boost you cannot perform another action, your character stops attacking, you cannot hit an active skill or feat button, I've tested this plenty of times with the old fighter action boosts, you cannot cleave, trip or even attack within the first two seconds of a boost so it's really an 18 second boost even with auto on or off... technically the first 2 seconds of a 20 second boost is unused which i suppose constitutes a DDO round? They should label it as 18 seconds.
I feel it's a step in the right direction but still the new HV is not that great of an enhancement line. HV would be a more useful emhancement as a +2 passive one to a skill, or to-hit, or damage, or DC of your choice. Plus what they should do is add another 7 enhancements to the human race since there are only 4 (technically 3). Choice is versitility.