Refueler
Well-Known Member
Luff foils are very common on race boats - they permit headsail changes without being bare-headed.
on race boats with head foils.., the halyard tension might be adjusted several times in a single weather leg.
The presence or absence of a foil isn't really that important - you can still get all the benefits of adjusting halyard tension even with a foil.
the primary effect of luff tension is in draft position - increasing luff tension moves the draft forward. In the simplest case, you might add luff tension just to counteract the natural tendency for draft to to move aft as the wind increases.., to keep the maximum draft in the correct position, fore and aft.
I am well aware of draft and so on ... having raced and successfully ... but with a furling gear groove - I find it hard to imagine I can get same amount of effect as with a hanked on sail.
Anyway - the OP IMHO was not asking in relation to draft / racing or similar ... I get impression he was asking in regard to CHECKING and re-tensioning if halyard etc. stretches.