Well, brother Eureka,
Are you trying to embarass an old man here??
In my old age, I have been a one shot wonder for a very long time, can't remember if I ever had two shots in the same session - come to think of it, may be once in a FS session, got some BBBJ in the shower and can't hold back, luckily the lovely lady didn't complaint about my quickie CIM (but as soon as I shot she opened her mouth and let go any way). Did managed to get it up again when in bed and have a second shot inside the 30 min, only happened once and that was many years ago, I won't try that again.
In terms of holding back during massage, well, there are only a few very special ladies who intentionally want to prolong your pleasure and holding off your climax for as long as the session itself, we are talking about a 15 min HJ in a 30 min session or 30 min HJ/B2b spanish in an hour sesssion and there has only been three of them, in no particular order:
Mimi, Lisa (QVB/SF) and Leng Leng.
And when you have the right rapport with these ladies, it would nearly be a game that she wants you to cum, but you try to hold on, then you want to cum and she won't let you, and the roles between us changed a few times during that one HJ process, absolute golden moments!!
This is what RnT is all about !!
To cum or not to cum yet !!
Cheers