Interesting advice from Amel  I think it's a bit odd, frankly, and it seems not to have come with a "why" do this..

I rather think the logical adjustment, which I've done, is to have it simply and gently snug up against the "donut" gaskets AND have the pin hole in alignment. There is no strain or overload at all needed by the lifting motor.  

When, infrequently, we insert the pin for boisterous sailing, its taper on the end picks the motor up only about one more mm when inserted and it goes in snugly, keeping the weight of the motor off of the lifting mechanism. Then we "pop" the down switch for a second to totally unload the lift motor. And we rotate the pin behind the locking post.

I should think a "strong squeeze", as you (or "Amel") put it, will compress the donuts a whole lot.  Eric (or was it Bill?) said he squeezes up about 10mm, almost 1/2 inch - I don't think the donuts are even that thick, so when not pinned that logically means they wouldn't be making firm contact with the BT box at all.. As I said, "odd advice".

Do you "squeeze and pin" every time you use the BT?  Seems a pain especially for coastal day-hops. I'd posit that most of the time most of us are day hopping and not pinning the BT (and shouldn't have to), so why not have the donuts be in firm and proper contact with the BT box all the time so they can do their job for those inevitable times when it kicks up a bit and you haven't put the pin in?

Oh well - lot's of ways to skin a cat.

Cheers, Craig SN68