Headphone amp as main amp?

Having heard gobs about increasing watts available as Ohm decreases, I have stumbled upon an interesting design from PERREAUX. It is their newest headphone amp which at 32 ohms seems to produce about 2.2 wrms....Isn't that supposed to be 2 watts? The headphone amp is said to be stable to about 8 watts....which makes me reason the following:

32 ohms....2.2 watts
16 ohms....4.4 watts
8 ohms.....8.8 watts....but then, I guess I am just attempting to follow a logic here, not all amps double as impedance is halved.

Nevertheless, can it be that this design puts out enough watts to run a high sensitivity, full range driver in a horn cabinet?

I wonder....not that I was going to try this.
There has been a ton of discussion about the Perreaux SHX1 as a headphone amp over at www.head-fi.org which you can find with the search feature there. I'm not sure if anyone has used it to drive speakers.
David Berning makes one that is also able to be used as a small amp. The MicroZotl, I think?
The microzotl which puts out about 1-2 w will drives 92 dB speakers very nicely in my home office (moderate volumes of course) and 95db horn speakers in my 14 X 22 living room to very nice volumes.