Hi Jim,
I read somewhere, a few years ago at least, that this less-summer-ice=less albedo positive feedback theory has not worked out due to the fact that open water (where the ice was previously) allows evaporation which then leads to more clouds. The increase in clouds, coincidently, provides the same albedo as the ice did. Therefore, no change in local conditions absorbing more heat. As more than a few studies have shown, the heat that has caused the ice to melt, is not home grown but advected, either by ocean currents or air currents, from places in the south,
Cheers,
Richard Hanson