Reinvented Regression testing

So many teams are abandoning regression testing in the agile era since it requires too much time. Usually they use the ‘retest all’ technique and their testing efforts are increased in each iteration. The biggest question is:is there a correct way? Gjore is not quite sure about that but definitely knows a more useful approach.
Reinvent testing by introducing fresh Ideas and changes so you avoid the well known "pesticide paradox". Reduce the timeused for testing and speed up the time to market.