"First, the "One True Value" itself of a share depends on how willing management is to do lots of buybacks. If it's a firm that does buybacks only at deep discounts to true value, it's a good firm and true value is higher. If it's a firm that does buybacks at all kinds of valuation levels, it's a worse run firm and the true value of a share is lower. The more the buybacks are a good idea, the more they're a bad idea!" - Mungo

I think a lot of this fed into Buffett's reluctance to buy back shares. Most of us recognize that it was an anathema to him for it to appear that company executives were managing or influencing the stock price. He knew that once Berkshire started buying back shares somewhat regularly that it wouldn't be too hard for people to figure out at what valuations Berkshire would buy at and that valuation would result in a fairly solid floor (by floor I am saying the stock would generally trade above that valuation for most of the time and even when it traded below that it was never drastically below it). As a result, he only wanted Berkshire to be a buyer when the stock price got to be a bit ridiculous from valuation standpoint. He didn't want the valuation to be conservatively measured; he wanted it to be CONSERVATIVLY measured.

He knew the more stock Berkshire bought back, the less opportunities going forward Berkshire would have to buy back stock. Buying back stock at more aggressive valuations than the real conservative valuation he used meant he would mostly only get opportunities in the future to buy back at those aggressive levels. It was a self reinforcing mechanism that just generally reduced the value of buying back shares. Like you mentioned, the more aggressively it is done, the less value it brings, even going forward.

I think Greg realizes that buying back shares is never going to be a huge driver of value, so he just figures why worry about it from a theoretical standpoint. Just buy the damn shares at any level below the "One True Value" slightly conservatively estimated and do not worry about it. So basically, I think there is going to be a new semi-floor under Berkshire (can still be fallen through whenever all hell breaks loose) because Berkshire will be buying at much higher valuations and buying larger chunks.

For better or worse.