Unworthy1 wrote:
"...I swear there's a SunTour DT lever with a very compact ratchet mech that looks like one of their stylish Superbes, but I can't find it in Velobase...must be very rare or I imagined it."
You're right, those were the trim-looking Suntour Sprint levers that had the very fine-tooth ratchet in them. I bought a pair back in 1985 or so from Nashbar for my Cannondale R300.
True Retrofriction levers use a spring-wrap clutch instead of a ratchet, so there's no friction adjustment at all.
The beauty of that is that the positioning is infinite (no click-stops at all), for better feel and greater resolution and more-precise movement.
Shimano made perhaps THE first, true Retrofriction lever in the early 1970's!
They called it Unishift. Rather long and plain-looking, but with rubber tips, and delivers race-quality actuation just like Simplex's version.
Shown in foreground:
Shimano also made the "beer tap handles" in the VERY early 1970's that I saved for 15 years(!!!) before finally installing them last weekend on my 1972 American-Eagle / Nishiki Kokusai:
