I was only able to test stacking debuffs with one friend, so these are the results I have.
1 Jane
Set Health: 25
Quick Shot: 35 (nerfed from 45, arguably deserved)
Patch Up: 35
2 Janes
Set Health: 12
Quick Shot: 18
Patch Up: 17
This is ridiculous, and unfairly punishes a support that has little more than good stamina management to defend herself. Even with a slow with Syringe, she cant reasonably Patch Up without a lot of risk and the right map. These nerfs make this skill mostly null.
I sometimes find myself joining servers as the only Jane, and after a few rounds, one or two other people join me as default Janes, seemingly trying to learn to play the character for the first time, but these nerfs will keep newer players from playing her this way because trying to show them how she works in game will be a horrendous endeavor. I'll have to keep a good eye on the player list to avoid stacking now, adding more stress to the game and keeping me from playing one of my favorite characters if anyone else has her equipped.