I found this puzzle disappointingly straightforward. I downloaded it at 16:00 yesterday — thanks, tatters — and finished it at 23:40 despite also watching BOTH Euro quarter-finals, solving clues while the Italian players practised their Oscar-hopeful roles as "man with excruciating injury".
As has been mentioned, the only head-scratching required is the meaning of the phrase "...two thematic in name only". How are the other examples thematic other than by name?!
[ kitsune (#10), as the preamble states, the paired letters give the thematic "context" (in the meaning of its second definition in Chambers) — there are thematic examples which could be found in other geographical locations. ]