Khandro...there may be many reasons that absent fathers do not make any contributions. Fecklessness is a major factor, I will admit, but its not the only one.
Perhaps the father is dead, or in Prison, or out of work ? Perhaps the father is is in work but paid so little that there is no money left to give ?
But its a mistake to think that WTCs are only paid to single Mums. WTC's are incredibly complicated, but this BBC link goes some way to explaining how people qualify ::::
http://www.bbc.co.uk/news/business-34572807
Most of these are just the kind of people that the Tories are saying that they represent. If these changes go ahead, in the way that Osborne had formally intended, then they will hurt the very people that we should be encouraging.
After all, the idea of this benefit is to encourage people to work.
its going to be an interesting day in the House of Commons !