Tory rightwingers only want a referendum on Lords Reform so they can delay any change at all. If changes to a second order chamber require a referendum when an elected chamber was in all the major manifestos of pretty much all the parties, then Lib Dems must require a referendum on boundary changes that radically alter the result of the next elections to the main chamber.
Or to put it more bluntly, if the Lib Dems give in to the Tories on this (once again), what has their 80 year wait for power been about? Slightly increasing tax allowances for all basic rate payers is all very well but if they get nothing on constitutional reform, which is what the Lib Dems are really supposed to known for, what is the point of the Lib Dems. Even the tax changes are easily reversible over a few years and only help the poorest earners if taxes are increased on the rich in other areas which has not happened.
Oh dear, the Lib Dem members and back bench MPs had better box Clegg's ears on this and tell the PM. Back out of Lords reform and you can sing for the boundary changes.