GMO co-founder and chief investment strategist has been arguing for months that we are witnessing the creation of an enormous asset bubble, but that it will likely run for a couple more years before it finally busts. Now he’s found another reason for the current bull market to keep running even though he thinks valuations are already too high: a frenzy of new deals. “Don’t tell me there are already a lot of deals. I am talking about a veritable explosion, to levels never seen before,” he writes in GMO’s second quarter letter. The disappointing recovery will drive an explosion…