Automatic queries were banned because they were flooding the network (it was a long and difficult discussion--no one wanted to give up such an obvious advantage).

If you use the manual "repeat search", LW can often build up a list of enough alternates for popular files that you can find some dl's will complete overnight.

As for why one client finds more than another, it's mostly coincidence. There is some preferencing that goes on (LW's connect most easily with other LW's, etc).

The developers do most of their discussions on the GDF http://groups.yahoo.com/group/the_gdf/