just plain full of it
It means that as a senior you are full of the wisdom of the ages etc. etc. or maybe just plain full of it.
I suppose it gives people some sort of indication as to how long you've been around the forum.
I've never seen anyone give 'off the wall' advice here anyway, they'd be corrected/disagreed with rapidly if they did.
This is great forum, I used to participate in a working dog forum, people used to attack,denigrate and revile other members. Theres none of that here.
Old Stiff: 42