I would not call the difference between turkey and chicken "subtle".
But some would, and that's the point. Some people can taste differences more than others.
If different starters produce differences of flavor as significant as turkey and chicken, you're right; [...] I don't doubt starters can taste different, but is it the starter itself or the conditions of its growth?
Apparently you didn't read the document I provided, or didn't understand it. Under the exact same aerobic growth conditions, Lactobacillus casei can produce as much as 11.9 µmol/mL diacetyl, while many of the other lactobacilli don't produce any at all. That's like the difference between canola oil and butter (diacetyl being the main flavor molecule in butter). If you can't taste a significant difference between those two, something's wrong. Still others produce a much greater or lesser amount of lactic or acetic acids, again under the exact same growth conditions. The numbers aren't subjective. If they're vastly different, which they are in some cases, they're vastly different whether you or someone else genetically like you can tell. The probability someone will be able to detect more than a negligible difference, with deltas like those reported, is actually pretty high.
What you are failing to realize is one of the fundamental reasons organisms are grouped into different species in the first place. Despite their similar appearance or outward function in the world, some species are very different because they process their environment in a different way. Environment in this case can refer to atmosphere, food sources, temperature, etc. Some lactobacilli lack the genetically defined ability to use certain food sources and in turn create certain byproducts. That's essentially what's going on with some of the lactobacilli reported on in the document. If an organism just can't produce a specific chemical, it won't matter how you feed it or maintain it. You can feed cellulose to humans all day long but we're not going to turn it into energy because we lack the ability to produce the enzyme to do so.
Nothing you or I said in our posts settled this, it comes down to the facts.
It may not be settled in your mind, but I presented facts rather than an opinion based on a genetically biased, personally subjective, flavor analysis.
EDIT: So that you can better appreciate my concern, I'm not against subjective flavor analysis. It's what people sometimes have to rely on when describing what a particular pizza tastes like on this forum. It's the statements that teeter on the edge of equivocal and absolute that I'm concerned about. If you were saying that you don't find it worth keeping four starters because all starters taste similar to you
, then the issue of starter flavor becomes equivocal and we're done here. However, "There is not much difference, if any, between the flavor of different sourdough cultures in the crust."
and "in my experience it's a myth that it's the starter itself which determines its flavor rather than the growing conditions"
seem to impart little estimation. "In my experience" could refer to factual findings, but I doubt that's what it really means."I guess what I'm trying to do is give "permission" for folks to not be obsessed with mutliple starters like some of you are, but to keep one well maintained and use it for everything. [...] you don't need to go that far to make a sourdough pizza crust!"
I'm not one of those folks obsessed with starters. In fact, I don't use a starter at all because I can make a pizza crust I like without starters. So if I took your approach I could be telling people "you don't need to go that far to make a pizza crust!" Which, quite frankly, should be obvious to anyone without me having to say it. Maintaining multiple starters is analogous to having multiple dough formulas. The flavor differences can be huge for some people, even when the ingredient quantity differences look small on paper.