Unfortunately, most people don't know, which IMO is why one should continue to educate about these fish and their potential hybrid crosses, and what the ultimate long term results can be in this hobby.
Sure, the vast majority of people that have spent some time in the CA folder on MFK know about CA hybrids, but still we have new members ask every month to ID their hybrid rd/midas cross. Those same questions have been asked for years, even with all the threads, posts, and even stickys on this subject - yet still eventually someone will ask, again.
And keep in mind that for every member that reads these threads, possibly hundreds or even thousands of non members will also eventually read these same discussions, sometimes years after the fact. MFK is high up on the google search engine so its not just the regulars of the forum that read these discussions.
As far as some fish being easier to get mixed up. Unfortunately with genetics things aren't that simplistic. The offspring of two different species can look like one of the parents, a mix of both of the parents, or nothing at all like either parent. I've seen two fish that appeared to be the same species breed true and produce hundreds, perhaps thousands of offspring, then one day toss out a genetic throw back to an earlier obvious cross breeding. This is why keeping lines pure is so important, and why unless you have a trusted origin you can't be sure of anything, no matter the species.
Of course this is no problem for those that aren't breeding, and/or distributing the fry.
