I watched a couple of artics plough through the flood at Runnymede on Sunday. The marshall there gave the advice to the drivers to keep it in 1st and keep going and they went through at walking pace.
The pedestrian I'm sure wasn't there through choice or for fun so give her a break. At Runnymede several people were wading through from residences on the river at Bell Weir to get to their cars parked on the roundabout - what else where they supposed to do?
I suspect when she started out the oaf in the yellow truck wasn't even there judging by his speed.