I'm a bit surprised by how short the OP's chain life is. Granted I live in the drier climate of the Portland area, but I ride in the rain a good bit and pretty much only clean and lube my chain when it starts making noise yet I generally get 2000+ miles out of chains, and closer to 3000 since I stopped trusting the simple style of chain checker.

The one scenario where my chain life is under 1000 miles is chains used for cyclocross racing. That's a fairly extreme scenario, both in terms of how hard I'm mashing the pedals and what kind of muck the chain is being subjected to. I guess the hillier terrain of Seattle might approximate the extra mashing I do in a cross race, but I wouldn't expect the muck factor to be any worse than my rainy commuting. Could it be a consequence of lubing the chain without cleaning it first?