The number of time you can hack a portal does not get reset when you Jarvis and capture it, it does however get reset when you install a heatsink. Added to that, a newly installed heatsink allows for four additional hacks within the first four hours. Source: https://plus.google.com/108020987035258478791/posts/cZo1X1mk3Je
For one player, the best strategy seems to be the one you gave, but you get more hacks out of it because of the 4 mentioned in the link . Additionally, if you first hack and then install the heatsink, you get one more hack out of it. So, ideal strategy:
Capture, hack, place multihack and heatsink, which resets the burnout counter and also the timer. You can then directly start hacking again, 20 more times with a 90 seconds cooldown. Virus, destroy, capture, repeat the procedure. Depending on whether the 4 additional hacks also resets you then get another 21 or 17 hacks. So either 42 or 38 hacks. 2 times with no cooldown, once with the time it takes for you to recapture and the other times 90 seconds cooldown.
If you do this, please report back. I'd love to know if this actually works as expected.
For two players, the best strategy as far as I can see is thus to install two VR Multihacks and a VR Heatsink, hack until burnout (26 hacks) , install another VR heatsink and that player can hack until burnout again ( hacking once every 58 seconds with two VRHSs)