2002 was the illfated experiment, but its not been uncommon to see briers fill in at 1 mid game due to injury.

He did it twice for 2 games
in 2001 when we had Walters at 6 and Langer 7, then Walters left after 2 games
in 2002 when Anderson wanted to play Briers at fullback in defence so he wasn't tackling as much, and then stand off in attack, that lasted 2 games as well

He did it twice for 2 games
in 2001 when we had Walters at 6 and Langer 7, then Walters left after 2 games, so Briers went to 6 and Hunte went to fullback (where he was quite good that season)
in 2002 when Anderson wanted to play Briers at fullback in defence so he wasn't tackling as much, and then stand off in attack, that lasted 2 games as well

Versatility is the key nowadays. Generally we need players to play 1 plus another position. Bridge does it well (apart from half) put him at 1 or 13 he does well. Grix has been fab though and our most consistent this season in my opinion. You can literally play him in any position the park and he will fill in admirably doing his very best whatever the circumstances. You get the sense he generally loves being tested each week through playing different positions/roles within the side, he revels in those situations when he is under the microscope. Each week he has grown and grown more in stature in the side, he is quickly developing into one of our indispensable players.

grix has been great for us in every position, as people have said any player can player a lot of positions but i think versatility is when your performance levels don't drop when filling in that position.