Eric (Tuco) and I just came back from a 3-nighter in the Pemis... Might be able to answer some of your questions though I lost count of the stream crossings on Bondcliff. We started on the Garfield Tr and stayed the first night at 13 Falls (Caretaker is there, didn't ask him how late he stays there though). Little did I know since i've never camped in the Whites there's an $8/person fee. Well, lets say that we didn't stay in another campsite although we were planning on staying at Garfield Ridge on Sunday night.
We camped on night 2 about a mile up the Bondcliff trail from Wilderness at a stream crossing. Not one of the Black brook crossing but on my AMC White mountains map, is the second stream that feeds into the Black Brook..
That area is very thick but since I wasn't familiar with the area and I knew once the trail headed north, it would be hard to find a spot so we decided to camp off the trail but not far from the stream. The camp we had was very very marginal though. The next day, as we climbed bondcliff, I noticed the forest opens up a lot and there are most likely legal campsites in this area that is a helluva lot better than the one Eric and I stayed at.
The second day, after going all the way over Bondcliff, Bond, etc. etc. and at the Galehead hut, we decided to find a site off the Gale River Trail rather than stay at Garfield Ridge so we hiked down and found a spot next to the Gale River. Nice spot on the other side of the river.
I know there was a falls and stream crossing somewhat after the real steep climb to Bondcliff but I don't know what # crossing this is that you all talk about. It is full of large boulders and if you look out, you look into a ravine before you cross it and head up some more. This stream is definitely flowing and definitely filterable. At least as of 8-29/04 when we went by. It rained ALL NIGHT on saturday night and we had about a 1/2 hour of intense tstorm pass by on Sunday night, all heat related storms that flare up just past sunset....
Jay