Indeed though Mercenary was book 4, one did get Citizens of the Imperium which had a lot of non-military careers too. If one counts scouts as non-military, fully half of the original careers are non-military. There was a definite duality though, though I also think that Marc meant it as more representative of the era when every male had served in the military, he is a decorated Vietnam veteran. His example of the game in "Understanding Traveller" though is all narrative, and no rolling, others I think wanted a war game, not surprising as that was GDW's stock and trade. It was way more lethal than RuneQuest, combat usually lasted a few turns before people were out, surprise was key, if you got shot you were pretty much done. Once Book 4's Gauss Rifles were used, they were like death rays, killing everything.