AFAIK there is no scientific evidence for feminised seeds resulting in more hermaphrodites, and hundreds of thousands of growers around the globe have been growing with feminised seeds for well over a decade. Feminised seeds are more popular than regular seeds even with their higher price, and they wouldn't be around all these years later if they were fundamentally flawed.
When feminised seeds first emerged on the scene all those years ago it seems there was at least some level of HOSTILITY from some breeders, many who had no experience with creating feminised seeds but were simply against this "artificial insemination" route, and that seems to be the main root cause of the "feminised seeds = hermaphrodites" myth/theory, and why it still continues to this day, even though nobody makes posts about how many hermies they got from feminised seed any more than they do about regular seed.
What we probably can say is that the vast majority of people growing with feminised seeds never encounter hermaphrodites at a level any higher than they encounter hermaphrodites from regular seed. Indeed, the only hermaphrodites i've ever encountered where from regular seeds, I've never encountered one from feminised seeds.
Of course that doesnt suggest regular seeds are more prone either, it just means some strains have monoecious and/or polyecious genetics (many HEMP strains do), and hermaphrodites are inevitable in those strains, regardless of whether feminised or regular. Blueberry is just one well known example of a strain which can produce hermaphrodites, and this is acknowledged at Dutch Passion's website.
You also mentioned stress, but again there's no scientific indication that plants from feminised seeds are more susceptible to stress than plants from regular seeds.
Feminised strains however DO naturally create some genetic issues that've been discussed in other threads - this is a non-issue if all you want to do is grow and smoke a female (which is why feminised seeds have proven so successful), but if you're BREEDING you should always work with regular/non-feminised if possible.