When has the doctor ever been able to work the tardis??
It coould be the first Series to have companions who are possibly more tuned in than the doctor.
"Doctor Look out, its a Dalek !!!"
"Oh.....erm.....wheres my errr.....you know......"
"Yea yea yea...thats the one. Chip anyone ??"
Think of the wacky/zany adventures they could all have