Lets use Hardy Chicago as our example:
My current personal theory is that the many Hardy Chicago types were all originally the same fig. For whatever reason Hardy Chicago was spread throughout the world and was grown in these locations for years. Like any fruit or vegetable variety grown in the same location for years, it will slowly adapt to its environment changing characteristics. That is why you see all these minor differences between them. Even the differences in taste. Dotatto is another great example. Found all throughout Europe highly valued for its great commercial traits. IF you were to attain a number of Dotatto's even from just Italy, you would find all kinds of minor adaptations.
I believe a lot of folks misunderstand the point of view of the "lumper" classifying these figs. I don't think these people (including myself) are claiming that every fig within the grouping are 100% the same. While very possible in some comparisons, it is simply that they are so similar it doesn't make sense to have both in a small orchard. Opinions vary and minds will probably not change today, but as long as we are open to change, I think that's enough. In the meantime, we ought to be focused on the varieties that are different enough within these categories that we should consider growing alongside others within that category. And that well.. that presents a whole new set of challenges (like growing conditions), but if a seasoned grower is telling me that Persian White is different by a considerable amount from say.. Atreano and here's why, I think we ought to listen. I would love to hear more regarding that.
Some examples regarding differences in taste: Malta Black and Azores Dark (Sao Miguel Roxo) produce honey throughout and sometimes even at the eye. For this it is sweeter and even has a different berry flavor than your typical "HC Type." White Triana while very similar in appearance and taste to Persian White, Atreano, etc.. but it has a more intense/complex berry flavor than the others within this category that I've tried. The texture also forms a really pleasant thick gooey jam further along in the ripening period. I had a Nero 600m grown in California that blew me away. It tasted of dark cherries. This October at Mario's I tasted an unknown fig similar to Nero 600m that was dead ripe with a similar flavor. Something I've yet to taste in my own VdB types.
There's also a whole host of other characteristics that can be quite different. Like precocity, ripening period, rain resistance, etc..
To prevent buying the same thing by another name.. you really ought to know what these varieties look like. They are commonly found among the community and have many names. Commit them to memory. The leaves, skin, size, shape, void/no void, colors, cracking/no cracking in the skin, pattern of the cracking, neck/no neck, length of neck & details of the eye, stem, ripening period, etc... and then do all of that once more if it produces a breba. Figure out what it looks like at various stages of ripeness, what it looks like waterlogged and in different climates. Not that easy to do, but you definitely can make it work.
I make the comparison to a dentist being able to recognize cavities at first glance. You could look at the x-ray and have no idea what to look for, but if you've stared at a enough x-rays, you'll eventually start to pick up each detail. Study these and I promise you will save a lot of time and money.
The varieties: Hardy Chicago - More synonyms than anything else Black Mission - Look for Maltese Falcon or Kathleen's Black to start English Brown Turkey California Brown Turkey Sal's Corleone Dalmatie Brunswick Longue D'Aout Black Madeira Bourjassotte Noire/Brogiotto Nero Green Ischia Atreano/Lyndhurst White/White Triana - The most confusing of all imo. Interior ranges from amber to dark pink. Peter's Honey White Marseilles VdB Celeste (Has many forms)
Get those down and you literally will be able to identify the majority of figs circulating in the US.