Please do not discuss (or even mention) current puzzles until after the solution is published. The moderators reserve the right to delete messages which do not have a valid Email address.
Re(1): prevent wind IP: 94.193.245.179 Posted on December 19, 2016 at 06:23:26 PM by Russ Cook
I cannot confirm the existence of the word pre-vent.
However, if it does exist then the meaning as you describe it does not equate to 'assist', but to the filling of the sails with wind. The 'assist' part comes as a result of the action of pre-venting.