Lol, I have to laugh at the 'lowering the VTEC' point giving more power crap.....
It might give the feal of it but wont actualy deliver any, it probably actually reduces it for 500rpm!
Remember that 'VTEC' is only the addition of an extra cam lobe which is VERY lumpy (if it ran on this at idle it would be as lumpy as HELL!)
When a certain level of revs is reached, the 'lumpy' lobe is engaged by locking the rockers (yes, they use rockers!) together which means the lumpy cam takes over fromthe two standard ones.
The i in iVTEC mean it also has variable valve timing.
Nothing overly clever about and nothing very new either!
So, on the larger engines the low down torque should still be ok as you run reasonably large valves on reasonable cam lobes.
Its the small engine that suffer as they still need quite big valves to get max effect from the VTEC lobes.....this results in lower gas speeds at lower revs and poor output power.