Zerax, you are quite correct, and my terminology was loose. In practical terms, the hands-off approach with banks, which started in the Thatcher era, allowed for higher and higher interest rates to be applied, without the caps favoured by other countries. A major change was when it no longer became mandatory to put down1/3 of the price, when buying, say, a car on HP. Many dealers got round this by falsely increasing the actual price, stating the 1/3 had been paid, and securing finance on the whole of the "balance".
It is not really correct to say that an APR of 1400% is usury, but in my mind it is just that...the charging of exorbitant interest rates...but not illegal, as you rightly said, and not "abolished" by Thatcher, as I wrongly stated. It's also fair to point out that pay-day loan rates have to be stated as APR, which has the effect of "inflating" the rate, as most of these loans are designed to be repaid within a month or so. Nevertheless, in my humble opinion, it is morally wrong to allow the charging of such high rates as we often see nowadays. I regret having pulled this thread off-topic, sorry!