I get some variations of what Satyrcum described in his own experience. Most common for me (about 90% of the time) a little bit of precum will seep out (4-5) drops with no leakage of semen before ejaculation as the guy in the video was having seconds before the actual ejaculation.
If I have had not had sex for awhile ( a week or so) and have been aroused for a good while over an hour, I will get more precum but it will not flow out and no semen still.
More rarer has been I will drip precum and I can feel it sort of pulse out at the base of my cock, the fluid is viscous, clear and thick, partners have pointed this out. Intense visual for me and further arouse me. If I have been edged or have been edging, late arousal phase, the seeping fluid will turn more cloudy, thinner or watery. On some of those occasions as I am approaching the PONR, my cock will start to freely ooze out semen as in the guy on the video, I feel the fluid building up in the base of my cock and I guess my tank get overfilled and it has no where to go but out and I am drooling and dripping cum but this at the last few seconds before cumming and lasts for about 5 seconds and then it all comes out as I've gone over and ejaculation commences.
Hot video, too bad those moments aren't captured more often.
Satyrcum excellent breakdown of the male arousal and ejaculation cycle for guys. I think we all get variations of what you described, a few manage to get the great volumes of precum or cum you described. I envy guys like yourself.