Good question.
There is already an implementation for the mimblewimble protocol, that is already working: https://github.com/ignopeverell/grin
But it is not proven on a "real" blockchain afaik.
I think you are right, grin is looking to implement the MW protcol - testnet at present with intent to release the end of 2018. A couple of other privacy coins (ie. monero) have suggested they might implement the protocol if it proves successful. So was just curious if this was something the deeponion devs were watching the protocol and considering if it proves itself.