There are things you do when you're writing that are so fun to do it's almost like they're private jokes that are amusing to you but no one else is going to enjoy them nearly as much and you worry you're going to have to take them out in the end.
A man ninety years old was asked to what he attributed his longevity. I reckon, he said, with a twinkle in his eye, it because most nights I went to bed and slept when I should have sat up and worried.
It's just a logical guess that they are very very wise to put someone from the old series in it, and if you had to choose, it would be a very difficult decision.