The usual assumption for the super-DX across the Atlantic from Europe to the Caribbean and S.America is multi-hop sporadic-E. Certainly the contact to K1TOL that I made a few years ago was by this mode.
But, with the recent questioning of the mode for the Europe to JA path on 6m in summertime, I am wondering if mesospheric cloud reflection is a possiblity for other extremely long paths too? YV and other places on the north of South America is some 8000kms away from here, yet people seem to work such distances every summer on 6m.
I'd welcome your comments and views.