I'm open to the idea of getting a watchlist. At the very least it'd help prevent FNM players from buying into decks a week before bans.
Some thoughts:
-Things like Simian Spirit Guide would probably end up sitting on the list for years at a time, making the watch list pointless for obviously degenerate cards. Combined with R&D's bizarre timing, it might not actually help stifle the outrage when justified bans like Top happen.
-Every new addition would be treated like a ban announcement financially, making it a "new ban list" in terms of people getting pissed off.
-Knowing WoTC, if there's any outrage whatsoever behind putting cards on the list, they're gonna postpone putting cards on it until it's too late.... making it have all the problems of a real ban list, but without actually getting rid of degenerate cards.
If done right, I like the idea. I have my doubts it would be.