OK, how I see the various return measures:
ROI, proposed by Mr. Pete, is return on investment. To me it gives the sense of I invest in various bottles and I get a return; there is an obvious confusion between the personal return (I greatly enjoyed this $10 bottle 15 years later even though it was largely point-free) versus a crasser financial return (I got a case of wine at the initial release price and was able to flip it after it got seven silver prongs from the Wine Schnauzer). I am sure Mr. Pete meant the former though the confusion is unavoidable and it makes those who use this term sound mercenary.
ROA is a measure more associated with the operations of a firm; perhaps I misunderstood the analysis (or the humor) but I saw the return on assets as somehow indicative of what I get from either (the return) from my physical (cellar) or human capital (knowledge derived from tasting and communicating), that is the assets in question. Some people who know a lot about wine may not have the time or the money to purchase the right wine at the right time and so may earn lower ROAs than those who are lucky (say they run into a friend at a wine store who says back up the truck to buy X and they actually have a truck).
IRR, the internal rate of return, was my attempt to be humorous; given that wine is a consumption good, drinking great wine is the best reward for a wine collector. I do not think much about the value of the bottles in my cellar (I almost never sell wine though I have offloaded a few bottles at charitable auctions that others might enjoy more than I would). IRR also has the feature that if the future cash flows change signs the right number of times, then the returns can be imaginary. [Geek note: IRR is the solution to a polynomial and if there are the correct number of negative coefficients there may be imaginary roots]. I find that sometimes may wine purchasing has an imaginary return, especially when I think of some of the white burg still sitting in my cellar...