Oh yeah, I meant to do a whole thing about how those changes are harder in adults then children but they do still occur to a less extent. No crushingly relevant, but worth remembering
This though: "I'm not sure reinforced neural connections are passed on in genes."
No it wouldn't be passed on in genes, but it would, or should be passed on in morphs. It's more than just the DNA molecule changing, it's the expression, the placement. And this is were my conundrum comes in: really memory, sentience, instinct, abilities both cognitive and bodily are, presumably, contained in the physical vessel. Assuming that this isn't stuff locked up in some incorporeal soul, that it is retained in the body in some way we don't yet understand, a morph should have the originals body. And thus a similar mind.
Really, from the science perspective, I can't see a reason why a morph wouldn't have the original's mind, memory, persona etc.
It comes down to morphing theory. Can you morph a baby tiger from an adults DNA? You shouldn't be able to, and then you should actually have that creatures....everyt hing.
Applegate doesn't do it for reason's given in the series, but a morph clone would be different than a genetic clone.
Really, I think the morality of giving it to a Yeerk is the same, but I do think it's something that should be kept in mind about morphing morality in general
Alternative method and ethics worth considering later: multiple host via splitting i.e. starfish