...realize that yield-on-cost was meaningless...

To be generous, I would say that it's *almost* meaningless.

A very high yield on cost is generally a sign that an investment worked out very well, over a very long time, which is a sign of a very good pick indeed, emphasizing two properties that you seek in a Buffett-type investment. It doesn't say much more than that, though.

It is indeed remarkable that the annual dividends that Berkshire gets on its Coke shares are such a high fraction of the original cost (around half?), but only as an anecdote. It's not numerically important or meaningful as such, but demonstrative of the fact that the investment worked out very well.

A better metric, rarely mentioned, is whether or not the real after-tax dividends you're received since purchase date have exceeded the real cost to buy the shares. After all, if a company can never manage that ability, it never becomes worth what you paid. (strictly speaking that reasoning requires that you count amounts which a company plainly *could* pay out but hasn't yet)

Jim