And so it might be that any phenotypic variation("occasional single variations" De Vries speaks for Darwin on(continued in the thumnail above)) that need not necessarily involve specific DNA genes (changing), could count as non-genetic "mutations", If you will.
Now what "single" means DOES mean not sexual but what else... well, Gould would have it not be more than rarely attached to "benefical" necessarily etc. Tricky thing language is indeed. There might be a small opening to dissent against the notion but it is small indeed.
I do not want to modify anyone's desire for a better constitution but it might re-p(l)ay to think about the thread with Huxley's words on the topic in hand.
quote: Evolution The Modern Synthesis by Julian Huxley 1964