Corrected entry: Episode 21, Season 3: Cirque des Merveilles. When Jesse is woken up in the middle of the night, he goes into the main hall of Sanctuary and is shirtless. He has no visible marks from being shot and operated on only 3 episodes earlier.
Revealing mistake: When Shalimar is getting ready to leap on Gabriel, there is a quick glimpse of support wires attached to her.
Emma: I grew up in Seattle, I can't believe I'm praying for rain.
Question: Why doesn't Eckhart like people touching him?
Correction: We don't know how much time has passed between episodes. It could have been weeks or months and therefore the wound would have healed.