- Having ML working on the 1Dx (and 1Dc): yes
Don't forget that quite a few hacking projects had serious trouble not because the hackers infringed any copyrights (they didn't, as far as I could tell), but just because they made the job easier for those who wanted to pirate things. See Sklyarov, geohot, graf_chokolo, Sony's comments on 2012 DMCA exemptions etc.
So, just the possibility of making it easier for someone else to infringe Canon's copyrights (e.g. by porting the 1DC firmware) can bring us into big trouble if we would try to port ML on the 1Dx.
=> no ML on 1DX.
I'm of the same opinion, but I think we should use the firmware of these cameras to learn a bit more.
This is not OK under neither European nor US laws afaik, because we don't have a 1DX and we are not creating any interoperable product for it, so we don't have the right to reverse engineer it.