There are 120 minutes of D time in a game if it doesn't go to OT. Slightly less if the Leafs get a PP because on PP1 they go 4F -1 D.
If we assume 2 PP's, the Leafs D will need to end up at a total of about 117-118 minutes played by D men out of the 120 minutes. (60 mins x 2 D)
If the Leafs play the bottom pair 10-11 mins, it means that the top 4 have to divide up about 96-98 minutes. So 24-24.5 minutes each on average. In what is supposed to be a rough game. One of the top 4 is 38 years old, and another is coming off a head injury.
I sure hope Keefe is smarter than this. Because this is how you go down to 2-3 healthy D-men from the current 4-5.