Right now if you are surrounded by a lot of creatures or hit multiple times by one creature First Aid will heal you based on the amount of damage that the last hit dealt you. This means something can critically hit you for 50 damage and then hit you again for 5 damage and your first aid will only heal you based on the 5 damage hit. This especially prevalent when fighting multiple creatures and one does more damage than others but is consistently slower so the one dealing less damage will always hit after the one dealing a lot of damage.

I would say First Aid is in a much better spot than it was in before the last time it was buffed and this was just an idea to make it more intuitive and versatile. I'm interested to hear opinions on the matter.