The former Rangers striker has struggled to find his best form since returning from a serious injury, but netted within 20 seconds of coming on as a substitute against the Minstermen.
Exeter were trailing to Ryan Jarvis' 17th-minute tap-in when Gow broke the offside trap and flicked the ball past the advancing Michael Ingham to draw Exeter level. And the 30-year-old sealed the win with a fantastic low strike from 20 yards to make it three wins from three home games for Tisdale's team.
"We spent a really hard week on working with Alan and what he does when he comes on the pitch so that when he comes on, he makes an impact," Tisdale said. "It didn't quite work for us when he came on at Morecambe last week
"We sat him down in my office and discussed that when he comes on and he plays on the right, or up front, or on the left, what is he going to do and it was a really useful chat.
"I wasn't expecting John O'Flynn to come off, but Alan came on and did exactly what we discussed. We want him to be focused on what he can do because it can be hard for a player to sit there, sometimes they can drift and go off the boil. But he is on the boil at the moment, so that was a really useful chat.
"The first goal was a real pressure finish because it was his first touch, but the second was a really good finish. He kept his head over his knee and kept it low, there is nothing worse than the ball going over the crossbar - I hate that."