Older pooner here and like many who remember pooning as a young guy, 2, 3 sometimes 4 shots were all possible, but you know, older ...
MSOG depends.
For me, it starts with overall health, whole other topic, suffice to say take care of yourself in all aspects and MSOG is a lot more possible.
When I want a 2x date, I let my SP know we are going for 2, so shot 1 happens in the first 15 minutes. Then half an hour of massage, cuddling, me taking care of her, etc, then work on shot 2 in the next 15 minutes, or whatever total time I'm in for and time it all accordingly.
But overall, if the date is hot, passions are out front and center, one good shot gets it for me.