Glenn Ashby seems to think so :

http://www.taipan.asn.au/Tips%20and%20Tricks/Resident_expert.htm

he says :

"To make the sails last. it is ESSENTIAL that the cunningham be let of before big sheet is eased around the top mark for eg. Even in a big wind I always let of half the full amount to avoid over stretching of the luff as the mast straightens from being super bent fore aft. I thinks sails can last up to twice as long by doing this. If you dont ease it it is like pulling the cunningham another 2 or 3 numbers down."

You guys can all find more Taipan trim and tuning tips on the official Taipan website (part is written by Glenn himself) :

http://www.taipan.asn.au/

by clicking on tips 'n tricks

Wouter