As far as I've heard, only 4000 PWs have been taken, and there have been no large contacts (beyond a few at the border) with regular army forces. Well there was one group that tried to go south from Basra that the Brits lit up. There haven't been large movements over the roads either. There have been occasional reports of whole divisions surrendering, but they have all turned out to be false.
That this means the regular army has "laid down its arms", rather than that they are waiting inside cities, seems to me a mere guess. If they aren't PWs, how would he know? Abandoned equipment I suppose, but we haven't yet gone into the towns where they were deployed. We bypassed them instead.