[fasterik]

I think the question isn't whether (DOOM + 1) would have succeeded, but what they would have been able to accomplish with the Quake team if they'd all had the stamina and job satisfaction to make several games over the following decade. DOOM was already a massive success and they had the money to do whatever they wanted. It's undeniable that Quake was id's most groundbreaking game, but maybe (DOOM + 5) with the same team would have been even more so.