I don't know if it's been suggested before - hell, it might have been Locke's initial insinuation from his post further up this page, but the idea that the Dunyain are all grown from Celmomas' seed would solve the problem of the Dunyain women.
Doesnt solve the problem of women. It solves the need for males to procreate, but you still need nearly all the important parts - the egg (which includes all the organells within the cell, functionally, everything important), and a vessel to grow the cells in. Unless they have some inchoroi growth chambers, I assume they need women for at least the second thing, and while its possible to harvest and store eggs today it seems unlikely to me that this is the mechanism they are using to make little celmomas clones.
And again, making babies from the sperm of a single father makes all subsequent generations siblings, not clones.
Even if they had harvested eggs and used the same mother's eggs and the same father's sperm... yeah still siblings.
Getting genetic clones is a much more in-depth process than freezing some sperm and eggs. Check out a wiki page
https://en.wikipedia.org/wiki/Cloning for some basics.
They would need a good understanding of the Tekne to do this, given the assumption that the Dunyain are not all Cisharurim and any magic they do would make all of them marked, including the babies they made via magics.
Growing them from a stock is a viable theory, but calling them clones is just wrong, as far as I can tell.