There is one other major factor outside price and availability of other suitors that explains the ability of Buffett to court companies, and it is a big one not discussed in the DealBook article: Berkshire does not mess with the companies it buys.
Unlike most acquirers, who promise their Wall Street investors zillions of dollars in synergies (i.e. layoffs and plant closures) resulting in all manner of earnings accretion, Buffett leaves his companies alone, and that is a tangible benefit which any board of directors ought to consider when deciding what should happen to the assets for which they are a fiduciary.
In the case of Burlington Northern, for example, the ability to invest for growth, without the need to meet Wall Street forecasts, as part of Berkshire Hathaway has allowed the railroad to take advantage of a shale oil boom that has helped boost revenues by 40% and pre-tax earnings by 50% since the day the deal closed.
And that is good for not just the Burlington Northern railroad, and for Berkshire Hathaway, and for Warren Buffett...it is good for the Burlington Northern shareholders who chose to take Berkshire stock, a key point missing from the DealBook analysis.