I for one have NEVER use the HHT, as such, how/so/every! I do use the AHT [close to the base of the arm hair, by the way] and that's when I know I"m close, but, it does not mean that I WILL get a great BBS from that blade.
It does mean most of the time I will be within 'tuning' distance of a great shave,
that's my story, and I'm sticking to it.
As ever, tinkersd