Three years now using Duotone boom wings without a harness. Never had any wrist issues from just holding on. I've always been able to depower enough for a light grip and still point pretty high upwind. Down wind is always a light grip ( most of the time).

I'm ~77 kg and I like riding my 1250 sq cm mid aspect front foil when fully powered even though I could ride my 950 sq cm foil at higher speeds in the same conditions. IMHO it's just less stress on the arms/shoulders/wrists for this old guy while riding/tacking/jibing at a slightly lower speed. The delta between max speed and stall speed (the # that matters to me the most) is still about the same for the 950 foil versus the 1250

Only times I've jammed/twisted my wrist is trying to do quick re-grabs while learning handle pass (behind the back) tacks, some variations of a luffed wing 360 and occasionally while trying to flip the wing back overhead after doing the starfish thingy

mcrt said..
I do not use booms but:
I had chronic wrist pains when i tried to wing with my usual windsurf grip (front hand palm up).
I switched to a both palms down grip and it solved the issue.

I also found the same it feels like your wrist is twisted weird front hand palm up on the Slick SLS - especially when pumping onto foil.

Don't know about booms but I sure do recognize your physical complaints.
I switched from soft handles (Ozone WAsp's) to hard handles (Cabrinha Mantis V2) in january 2023 and had soreness in my underarms about 5 to 10 cm from my wrist. Not during a session, but the day(s) after.
It seems to lessen slightly, but can appear with certain motions (turning or lifting something in one hand, like grabbing a pump).

I do like the soft handle for that reason, I tend to like bend my wrist in a more confortable position and soft handles permit that. I'm a long time windsurfer and when I windsurf, I feel my wrist/elbow pain coming back. With soft handles it's not a problem, knock on wood!!!

I've only ever used a boom with Duotone wings and like the ability to slide my hands on it as I come from windsurfing but like you have noticed sore wrists especially after multiple days in a row. I wonder if the lack of shape in the boom loads the wrists funny. There are a few hard handle brands that are angling the handles, possibly trying to alleviate these issues/add comfort.

Solite gloves are the solution to forearm pump. They are pre-curved, easy to compress, and still have lots of dexterity. I have arthritis in my left wrist, so I feel your pain. Duotone is now selling the SLS Mini Boom which is carbon and very thin. Costs a lot but cheaper than drugs and therapy.

^ Tennis elbow or golfer's elbow? Golfer's is on the inside of your elbow and is aggravated by gripping and pulling.