Assuming that this represents the verdict of the party's tax commission rather than an attempt to pre-empt it, my initial reaction is favourable.
Radical proposals promising a 2p cut in the basic rate of income tax, funded by a green levy on air flights, and tougher tax rules for the wealthy will be unveiled by the Liberal Democrats this week.
My worry about environmental taxes is always that they may work too well. If people change their behaviour because of the new taxes, won't that reduce the amount they bring in? How would we fund our spending commitments then?
I expect a Conference row over the end of the 50 per cent rate on higher incomes, but the important thing is the overall effect of any package. It is wrong to make a fetish of any individual tax rate.