Even if it does not, you are vulnerable to a single sand grain getting in there.
Thinking aloud I suppose what one really wants is a bearing surface that exactly matches the pole on say 40% of the diameter which takes the load, and a fair degree of play on the rest of the surface... So on the fore end like the attached, at the aft end the same but inverted. I suppose it wouldn't be totally impossible with generous amounts of parcel tape... Or is there some obvious drawback I've completely missed?
Not something I anticipate having to worry about in the forseeable future though.
