Scotland Bill

I hope that the noble Lord might help me. Is he saying that he thinks this clause is too broad in its scope and that there should be some kind of constraint by way of criteria as to which taxes could be invented? As it stands, a wealth tax, a further tax on inheritance or a roof tax could be implemented, although a poll tax is probably less likely. Is he saying that, speaking for the Opposition, he favours some kind of procedure that would constrain the ambitions of a devolved Administration in this respect, or is he saying that this measure goes to the heart of the whole Bill and that it constitutes devo-max?