Best index tracking ISA?

nrsql

A paper did a calculation on two investment strategies. Mr Hindsight invested in the top performer in the ftse 100 in the previous year, Mr Foresight in the current year (if only).
For the last century (this was in about 1990) Mr Foresight of course made a fortune but oddly enough Mr Hindsight just about broke even - big loss if inflation is taken into account.

One investment strategy is to pick the period and percentile. eg. invest in companies 10-20 in ftse over the last week. If you look at all the historic results you can pick the best strategy - unfortunately that strategy wouldn't be guaranteed to work in the future (but you could advertise it on the gains it would have made historically which is what managed funds rely on).