From: Washington, DC
Yes, I agree on that, surely a swamp hex doesn't represent 16 kilometers of knee deep water, but just like motorized units, cavalry would be confined largely to roads, which there should be few of, and that would inhibit mobility.
well, I am far from a cavalry expert, and most of my knowledge about horses comes from watching Western movies, but I would think that cav would have decent mobility in these swamp hexes--they could cross fields and streams that vehicles could not, and I would think that at least in some cases it would be easier for cav to cross streams, etc. than infantry. Obviously they would struggle in deep mud, etc., but who knows what proportion of these swamp hexes is meant to represent true swamps?
As to supply, presumably it would be difficult for any units be get supply in these hexes, I'm not sure if it would be harder for cav than other units.