18s don't have restrictions against wing rotating masts. The main thing is no one has spent the money recently to try and get one to work, the current mast is efficient to an extent and capable of handling the huge loads generated. Providing no one else changes their rig design (currently CST Composites supplies the whole fleet) there is no need to change the design. It has been discussed in the bar quite often however.

They also do not have hydraulic rig tensioning devices. All the rig tension comes through a boat breaker, similar to a mainsheet set up on a cat (lots of purchases :P)

Cheerio
T_E