Gauntlet used a detection grid that held the coordinates of all the player and enemy values, as well as linked lists to handle so many possible enemies at one time. When they overlapped, sharing values, it triggered a collision. I think this would allow for as many simultaneous collisions as actuallly took place.
This is interesting extra material on Gauntlet, but sadly it doesn't have all the information needed to R-E the grid.
http://twvideo01.ubm-us.net/o1/vault...Postmortem.pdf
Page 33-34 briefly covers this.
Gauntlet probably made heavy use of the VBRs. I suspect the 010 was chosen for this reason in particular, to utilise its more dynamic jump tables? I'll see if I can find some more conclusive docs, but I'm unsure if the Gauntlet source is floating around for analysis. It may be though, as a lot of Atari source code was found in bins, and made available, some years back.