Intriguing inter-G propagation on 10m

This morning I am copying G4SPE at 195km on 10m WSPR. This sort of inter-G distance is not uncommon on the 10m band. I assume this and similar spots are by normal tropo. Years ago the RSGB ran evening 10m contests and decent inter-G QSOs were possible with 10W SSB/CW to dipoles.  Every contest evening I would work down south or up to Yorkshire. I assume most inter-G WSPR spots are tropo but some may be back-scatter. I am sure consistent JT9-1 QSOs (and WSPR spots) would be possible inter-G if there was more activity. Something to try in the quiet years on 10m?