I think Labour is stuck between a rock and a hard place. The vagaries of FPTP have turned against them. Instead of having 40+ safe lefty seats in Scotland that they could take for granted, allowing them to cling to the middle in England, they now have 40 lost seats that want strong leftist MP's. If Labour tacks left, they risk losing even more English seats to the Tories & Lib Dems. If they ignore Scotland altogether and try to make up the seats in England, they basically become the Canadian Liberals 
It seems to me that Labour needs to write Scotland off, and tack enough to in effect merge with the LD's, in other words, to just make that party go away. The policy differences between the LD's and Labour don't strike me as that great, if Labour just tacks a bit to the right.
There's Social Class. Labour is not and never will be a bourgeois party like the LDs.
