CABob writes (in part):

The point is that any of the methods you might use will arrive at the same cost basis if you are selling the entire holding of the fund.

I reply:

That's true, but different methods of calculation may divide that cost basis differently between short-term and long-term shares. As the OP correctly points out, performing FIFO accounting will give the same division as double-category cost averaging, but single-category cost averaging may give a different division. Specific identification is almost certainly not available (and in any event would be a waste of time and energy because it would reach the same result as FIFO) because it's doubtful that the requisite instructions were given at the time of the sale. --Bob