TI Le Dandy honing headache

[MikeB52]

Hi gents, I too owe lots to the senior members of this forum for their vids, blogs, notes, and posts.
Learning from them I have been able to become a competent honer of most razors in my collection, with the exception of the above mentioned Thiers.

I have the atypical 1,4,8,12 k progression of rocks now and can build and maintain edges on hollow ground German blades, wedge sheffields, and Frameback Swedish steel without issue. But this TI 69 LeDandy refuses to get sharp/smooth despite my attentions.
Last night I started with one layer of tape and good slurry on the 1k. 3 sets of 20 circles followed by 100 x's and then again with dilution, up to 4k to do the same progression with less pressure, etc..
Then I replaced the tape and added a second layer and returned to the 4k and went back up through with mild pressure.
Under the loupe I can see the two micro bevels clearly and feel I should have a good edge, but my shave lets me know to the contrary sadly..
This blade is becoming as frustrating as mandatory French in grade 7 and 8 was!! Lol.
May have to seek professional help, but I'd rather go with to see how it's bested..
Any ideas?
Cheers gents.