Much as Jimmy has been a legend for us I think in this instance Borthwick has made an error. I really hope Jimmy gets some game time but I doubt it. 12 is a funny position. At the moment there seems a dearth of good ones in the game.
It always feels that the role of a 12 is constantly changing.
Sometimes the priority is a straight hard running big guy to hold defenders, punch holes and offload.
Other times it's a second play maker to take pressure off the 10 and allow attacks to be launched in multiple directions.
Sometimes, the 12 should be a defensive rock capable of covering the 10 channel too, other times that seems to fall more on the shoulders of the outside centre with the fly half holding their own.
And in general, most fans would want their 12s to do all of the above.
If you have a powerful, running 12, the contents will be that they can't/don't pass the ball. Similarly if they're a distributor, there will be comments that they don't give a team any go forward.
The role of a modern 12 seems very complicated and is essentially a Jack of trades that also needs to be a master in them too