"What this means is that you do not pay any tax on interest earned by the Isa!!."

True enough - but the interest you get is hardly worth the effort.

The trouble with most of these things is that the saving you get by searching out the loopholes is liable to be pretty minimal for most people. Big savings only come in if you're loaded, and in no way need the money.

A radical simplification that gets rid of all the loopholes exploited by rich people is needed. I can't see why it couldn't be done. A maximum generic ceiling for the total amount you could save by all of them lumped together could be imposed, and set at a reasonably low figure.