selfie, thanks so much for the details! I guess I'll put CNC bits on the back-burner for now.
I picked up the dremel plunge router attachment and will try a few holes later when I get a chance. Hopefully a regular twist bit and a really fast spin will give a good enough result.
On another note, I picked up another blower. I was actually thinking of making an air cleaner for the shop. The big ones I see (e.g.
http://www.busybeetools.com/products/AIR-CLEANER-510CFM-CSA-CRAFTEX.html) are rather pricy. All one needs is something to move air, a filter, and a box - all easy to come by. This new one seems to move a lot of air, and may also be able to build more pressure. It's something of a different design from what I currently have (pics to come). I have yet to spend any time with it, so details sketchy at the moment. When the time comes, I think I'll try both - the better one will remain, the other becomes the muscle behind the air cleaner.
Earlier in the thread was mention of a mini - I may just try that as well. Some time ago i was given a pair of smaller blowers, so I might just put a mini on the to-do list. And in fact, perhaps before drilling 4k holes, I'll try fewer with a smaller blower as a test.