Query.
In Grey's tutorial, he makes an Instance(); function.
Considering this class is purely static, and Instance is never called, this function, and the static StandAlone* m_Instance, seem irrelevant.
Because the class is static it works as a singleton anyway, so the result is the same, but what it's trying to do seems redundant.
Comments
It is not necessary, and you are most welcome to change it for yourself if you wish!
EDIT: i still think it's better to delete the instance function in the tutorial for clarity sake, you can always make another tutorial explaining it if you need it.
And yes, i could change it, but i think it bad sport to change other peoples tutorials.