You are indeed correct. There is a huge amount of competition between the yeast companies so they MUST have yeast that is indistinguishable from that of their competition if they are to ever compete in the bakers yeast market, this is why they are essentially the same when it comes to flavor of the finished product...there is no "good" or "bad" but different is 110% unacceptable. We have looked at this many years ago and found that many of the differences in flavor were the result of incorrect substitution levels, incorrect activation (ADY or IDY) and age of the compressed yeast (CY) also played into it. When it comes to finished product flavor in a yeast leavened product yeast level, dough temperature, and fermentation time/conditions are the main driving factors in flavors associated with yeast. Finished product flavor is VERY COMPLEX and is influenced by MANY different things, it is so complex that the flavor has never been able to be replicated or synthesized even in the best flavoring labs in the world. You can get a cracker like flavor but not a bread like flavor which is close to that of pizza (think French bread) which is made using essentially the same dough formula as pizza.
Tom Lehmann/The Dough Doctor