Nigel
I don't buy the low yield arguement either. On the bucket and spade routes there's no such thing as high yield, nor probably on traditional weekend break destinations, such as Prague, Barcelona etc.
However, I seem to recall that due to the high numbers of inbound business travellers to BHX for events at the NEC and ICC, BA Regional actually had quite a lot of higher yield traffic on business routes. If EZY were to put resources into routes such as CPH, MUC, BER, ZRH (not GVA), MIL, MAD etc with proper frequency (minimum daily) then they would surely get better yield.
Unfortunately, these routes are already served, in the main, by LH and their Star Alliance mates so they would be starting as the new kids on the block, and perhaps, at this tough economic time, they don't want to take the risk.