-Hi Mark -
<br> You will get some varied opinions on this ,
<br>generally as much luff tention as possible seems to help particularly reaching with the spin. -
<br>
<br>-The only time I,ve experimented and let the spin halyard out is in light to med. winds running deeper allowing a fuller shape and opening up the slot between the spin and main at the top .
<br>-The same theory and effect as opening up the jib slot in lighter conditions .-which has proven to be faster .
<br>-hope this helps -
<br> best regards
<br> Carl Roberts<br><br>