<<<The key phrase here is "conservatively determined." That is parallel to "margin of safety." I disagree that Warren would buy shares without including some protective discount in his reasoning. Warren doesn't use a short term value for IV. He uses a smoothed value.>>>>

Based on some rather short comments on the subject of buybacks by Warren at the annual meetings(that I picked up), I'd venture to say that Greg Abel is the one behind the wheels over the past few years already. Why? Buybacks will make up the motherlode of capital allocation decisions over the coming decade and it is a great education/mentoring opportunity to estimate Berkshire's IV than doing the same with other outside businesses, where information is subject to interpretation. Warren can watch over the lad and that's a good thing.

So, if we are perceiving some change in the buyback regime, I'll chalk it up to a new bus driver.