Not a move I would support. Given the presence of company reps, email list users (which are done by FTers), blogs and twitter feeds from FTers, search engine blocking attempts are ineffective if the goal is to try to protect fare deals.
Also, not everyone is able to always access FT with the benefit of browser cookies.
Who knows what the advocates of this motion are trying to achieve. The horses are already out of the barn, and with fare finders working for the airlines and ATPCO having speed up its game, such attempt at fare deal salvation is not going to substantially prolong an airfare deal. Mileage Run Discussion may be another story, but that has much the same issue as that of the Deals forum.
If this motion were in place when I first came to FT, a lot of the best info I got about airline and hotel programs and fare deals would never have come my way.