It'd be a bit awkward to have Donna along for that - hee!
Perhaps it'd be him going there not to have it tweaked in terms of providing him, er, satisfaction, but to try to figure out what's causing it to go nuts. He might run around testing himself for having been exposed to certain substances or energies, and taken Donna to several places that are supposed to be restful or whatnot in hopes of avoiding returning to Karn.
If it's a situation where he's basically being dragged into his mindscape more and more as time progresses - which Donna normally sees as him blanking out at random but closer-together intervals - and it comes to a head in him crashing the TARDIS or spacing out in the middle of something else equally important, I don't know that Donna would leave him much of a choice.
no subject
Perhaps it'd be him going there not to have it tweaked in terms of providing him, er, satisfaction, but to try to figure out what's causing it to go nuts. He might run around testing himself for having been exposed to certain substances or energies, and taken Donna to several places that are supposed to be restful or whatnot in hopes of avoiding returning to Karn.
If it's a situation where he's basically being dragged into his mindscape more and more as time progresses - which Donna normally sees as him blanking out at random but closer-together intervals - and it comes to a head in him crashing the TARDIS or spacing out in the middle of something else equally important, I don't know that Donna would leave him much of a choice.