Yeah I’ve seen that.
However the above comment situation still stands, along with the contemplation of ‘How long is too long?’
That being said, with the new forum layout – People have been getting ‘new’ notifications all over the place and necroing threads unaware & accidentally. Heck, from another thread there was a guy who had the same ordeal with the ‘new’ notification and was only stopped thankfully to the warning system that popped up for the
‘ARE YOU SURE YOU WANT TO REVIVE A 3 YEAR OLD THREAD?’
Made me thankful my accidental necro was only 10 months 
However those that are sizzling under the barrier of the warning pop-up could still necro various threads for notifications that are presented as new, but are in fact rather old.
Source of other thread: