I think that particular video is a poor example of what forearm turns can be. I can’t deny the potential for sweat, but, confession, my hands sweat like crazy anyway, and I seem to collect plenty of other people’s sweat in swings and courtesy turns, as it is.
I disagree about weight. The difference is that the connection puts less stress on joints and therefore feels lighter, but is, in fact, tighter. At contra dances, doing a traditional allemande, where according to Rich we should find it easy to give weight, instead there’s a panoply of styles of mangling hands wrists and shoulders, flexing or flopping elbows, which result in all too few actually satisfying and well weighted allemandes, regardless of role danced. If it were easy for that allemande to be well executed and well weighted, wouldn’t it more generally be so? Wouldn’t there be fewer defensive variants?
The forearm turn is almost impossible to mess up, with fewer joints involved, and even when less weight is applied, is firm and close enough to result in timely movement. Whatever else can be said about it, it does not permit wide spacing between bodies, and people do automatically bend their elbows to something like the appropriate angle. There only being one angle to adjust makes it easier to fine tune, in my opinion.
Richard Fisher requested, I think, a description. To be as accurate as possible I asked my partner, who, like me, has been a long time contra and English dancer, as well as a MWSD dancer. (I have always danced at gay clubs, which, I understand may be zestier than average?, and he is a MIT Tech squares alum, which, being a college club, may also dance with higher energy than the club in the video) to simply give me a MWSD forearm as if we were about to, for example, swing thru. He gave me what I expected, and what I consider good form: full hand and fingers solidly on the meaty inside of my forearm, which let me do the same, forming a flat wristed, full hand through forearm connection for both of us. Instead of a W, you get more like a \__/ look. The outsides of the fingers are to a wall, the insides pushing at the forearm, like we pressure the hand in a traditional hold. It feels more like the whole arm is involved to me, less muscle action needed, only enough to maintain the arm position. We varied in how we held our digits, I had mine more open, he kept his flat, either way it functions like a mitt. Both of us used our palms to make the primary connection, fingers lighter. As in any allemande, the elbow and shoulder firm up to complete the connection. It can be very zippy indeed!
I’m still searching for a clear example in video form. I’ll let you all know if I find one from sources I have access to.
FWIW, I am exhausted from the last few years of the community arguing about words and terms. So I’m leery of us picking yet another thing to get exercised over. If anyone truly gets near perfect results from their teach of a trad allemande, I will adopt their words on the spot. Otherwise I’ll continue to see the leas than desirable quality of allemandes experienced as a pitfall of the hold itself combined with the usual humans being human, each with individual understandings, abilities, etc leading to highly variable execution, rather than a consequence of sub par teaching.