It would be a shrewd but very unlikely way of tweaking the lineup. Teams don't tend to make those kind of changes within the season. But the Canes dumping Bunting to get Guentzel was very shrewd, even if it didn't work out.
If the Leafs did remove Kampf one way or another, keep Jarnkrok and Hakanpaa on LTIR... they would have 4.6M of cap space with a 23 player roster. If you trade Robertson or Holmberg as part of deal to add upfront, you can add a 5.5M ish player. This is also with 100k dead cap space from Benning.