Steves & Gonk, I think there may be a semantic difference in the way you are describing the same thing. I agree that each side of the X-over would see a maximum of 100W (using the 7100 with 2 channels bi-amping). But there are both a high and a low pass X-over (assuming typical 2 way bi-wireable speaker with passive X-overs) therefore the speaker cabinet has a total potential of delivering 200W.

If the same speaker had jumpers between the bi-wire terminals, then the voltage would be the same, but the current would be divided between the two crossovers. Assuming (the impossible!) that the characteristics (impedance, phase shift etc) of the low and high X-over and their related drivers were identical in every way, then half the current would go each way and therefore the wattage would be 50W per X-over for a total of 100W per speaker cabinet.

The above is assuming that every item acts as the ideal and losses/shifts etc are not accounted for. I am not considering Charlie's suggestion of an active X-over, as I have absolutely 0 experience. What he said makes sense, though. If there is an obvious omission, please correct, as we are all learning every day.

Last thought: Since you have to double power for a + 3db gain, is it worth bi-amping for an SPL approach only? Gut feeling is no. . .

S.