In reply to Lady Fantasy:
youve got the right forum - especially if you want a multitude of opinions.
my 10p:
1) it would take several hours. 500m is long and the dynamics mean it will be fast for the first 250m then very slow for the next.
i regularly do a 25m tyrolean for work and its about 2mins across including clipping on and off.
over 500m it could be a 1:5 ration of time to:from the mid point.
2) not 1 man at a time. over 500m 3 at a time would actually make it faster by taking out some of the rise from the mid point.
much will depend on the rope used as it would need to be stronger (forces in traverses are dodgy).
getting an unconscious person across would be possible but very hard. would have only 1 other able soldier with them and probabaly a second rope to haul them from the far side.
unconscious person would be in a sling, sling seat or litter.
3) your pursuers could find whatever you need them to.
often pulleys are not used at all, but unless they have another rope to send the pulley back to the start for each man (more time) they will each have one.
by two pulleys, thats either to have 2 in rotation, or to use 2 at once so the load on the tensioned rope is less acute.
it would be very poor soldiering to leave a pulley behind, indeed proper tyroleans are rigged so all but the anchor is retrievable.
anything hanging on the rope would drop if the rope was cut from the far side, but if a retrieval rope was used for a single pulley to go back and forth the pulley could still be attached at the far end (in that case tho the good guys would have taken it with them).
it would help to know if these are contemporary soldiers or ww2-type stuff, as methods and equipment would be different - and theres a good chance you will find an expert on here on whatever era you have chosen.