After all the wonderful helpful suggestions on this thread, I decided to test my own theory that 200+/- on the D was OK, I hit the river about noon yesterday with cfs at about 220. Following TP's suggestions, I dropped in at narrow section near the hatchery. Sorry TP, it obviously wasn't running 1000 cfs, but I did find the nooses you so thoughtfully left for me handy in pulling rhodo limbs down to retrieve snags.

While the water was quick and I'm sore today from moving around in it (I'm old you see), it was doable. Fishing? Yes. Catching? Not so much. Tough to get the fly down at this velocity and mending was tough. Probably should have opted for bugger down stream. o-o
Later I went downstream, assuming that wider would slow speed down. (P = F/A ?) It didn't really make that much difference except in significantly deeper sections. This was before the Looking Glass confluence so there was no additional water being added. I'm not questioning the formula - too many other factors (streams other than Looking Glass, elevation drop, etc. plus I was estimating which is notoriously inaccurate - just look at my claims for length of fish caught!

Not rocket science revelations for sure, but it has been a while since I've had to even think about it, so an interesting day to say the least. In any event, it should give someone pause when jumping into these conditions.
Thanks for your suggestions all and I'm thinking about checking into a river board. Wonder how you would mend on that thing...
TB