That is just how I would like to be pleasured, with lots of fondling of my testicles and slow, varied strokes of my penis to build up a nice full load of semen.
I always hold the guy's nuts as I'm jacking him; as he starts to nut, I get a little firm with them and keep a nice grip on them as the man ejaculates. As he completes the release, I hold his penis calmly until flaccid.