Thank you all for the interest and the comments. It was a great experience--being able to share it with fellow BPL folks makes it that much better.
Mary: For July, the canyon bottom that week in July wasn't *too* bad. Last year was such a big snow year, the problem with going much earlier would have been access to the rims. If I recall correctly, the roads to Hat Point and Windy Saddle were still closed well into June. Really, Sept-early Oct would be ideal, but Nathan and I both teach, so it's tough to get a stretch of days off in the fall.
Michael: I'm just across the state line from Pullman, in Moscow. Good to know there'll be an BPL guy in the area.
David: I'd been wondering how your November trip went. Mid-April sounds interesting, and adventurous. I'd guess a person could get a ways up the road to Windy Saddle at the point, then use the bike hoping most of the rest would be clear-ish, just too many lingering drifts to drive? My understanding is, we're at something less than normal snow pack--might be a good year to try it.
Alfred: Wow--that's a big drop overnight. I would guess the drop overnight when we camped at Bernard Creek was only a foot or two. My guess is last year there was still enough flow upstream of the dams that Idaho Power didn't have to cut off the downstream flow as much to store flow for the next day's power production. We didn't get as far downstream this trip as Johnson Bar, but I couldn't have imagined swimming.
With regard to group dynamics: I've always got a lot out of articles that offered a candid look at successes *and* struggles of a hike, more so than accounts of things going perfectly. As I wrote, no way I could have done this (especially first time on the route) without a partner, and no way the dynamics could have resolved successfully unless that partner was someone as straightforward as Nathan. I look forward to many more hikes together.
Again, thank you all for reading and commenting.