Stock buyback strategy

Suppose I proposed to you a stock purchase strategy of the form, “when the stock is at a high or medium price, buy it, but when it is historically low, don’t,” what would you think?  Doesn’t sound very good, does it? It is the logical inverse of dollar-cost averaging.  Strangely enough, in the great recession of 2008-09, that is what we are seeing as the strategy taken by many high-tech companies.  These companies have been pursuing stock buyback plans for several years, but now that we are in a worldwide recession, the companies are (wisely) conserving cash and suspending their stock buyback programs.  But the very time that they need to conserve cash is naturally when business is terrible and the stock price is relatively low.  So, in effect, the program reduces to the strategy I already mentioned—buy the stock except when it is low. This is the very opposite of Dr. Henry Singleton of Teledyne’s successful strategy.