Are you referring to a pinned thread - one that is permanently affixed to the top of the page? (Locked would be one no one can post in)
Thing with locking a class post to the top is that doing it for one - we will have to start doing it for all.
If there is sufficient interest in the class then the thread will stay active and at the top of the forum. One example that comes to mind is in Electrics where the "Super Tune your Super Vee 27" thread has never been pinned anywhere and is more than 200 pages long - over 5000 posts in it. http://www.rcuniverse.com/forum/m_4752309/tm.htm
. There have only been 9400 posts in the sailing forum since its birth in 2003.
I would suggest an "Unofficial all things IOM" thread like the Electric Jet Boats have (with 4000 posts in it) http://www.rcuniverse.com/forum/m_6523863/tm.htm
. The above two threads have remained active for 3 and 2 years respectively - we could pin them - but interest alone has kept them alive. I should think there sufficient interest in an IOM thread that it would remain on the first page - there has not been a huge turn over of posts in the sailing forum.
By all means let me know - Start an IOM discussion thread - I can pin it until it gains momentum if you wish and go from there