I have learned around here that it's best to do what makes you comfortable. And if cranking the engine over a 1/4 turn, then hitting the primer does it for you then so be it. It doesn't hurt a thing (other than a drill motor here and there). For a long time I never primed anything, just coated everything with a mix of 50/50 oil and STP except piston rings - they just got oil. Now I prime them before first fire and prime with the starter if the engine has been sitting any length of time. Does it help? Maybe, maybe not- beats me but it makes me comfortable.
And yep, I have the old distributor version but I can see where on some installs that might be really tight with a drill motor attached.