I don't mean to pour scorn on the re-enactment as I have never seen the program your talking about.
However, I have seen similar programs and have come to the conclusion modern day western man is just too soft to cope with the kind of conditions our forefathers had to endure.
There was a series on the BBC a while back, where a group of average working class men had to live the life of a Roman Centurion for a few weeks, supplied only with the clothing and equipment an average "private" would have had back then.
They didn't last the course.
The Romans wore nothing but sandels on thier feet - whatever the weather. Our boys feet didn't last 2 days before serious foot rot set in. They had to revert to modern footware.
It wasn't unusual for Centurions to march 20 miles a day, and then spend a further couple of hours building fortifications for their new camp - all on Roman rations.....
Sleeping bags had to be supplied to our boys within a week before they all died of hypothermia.
We couldn't even handle the basics. The problems the Romans must have experienced with parasites, disease, and battle wounds wasn't/couldn't be considered in the reconstruction.
Iife was hard then, the people were tough - a lot tougher than we are now.
I somehow doubt your modern day colonalists are really toughing it.
It should be noted the Romans never managed to conquer Scotland <img src="images/graemlins/grin.gif" alt="" /> <img src="images/graemlins/grin.gif" alt="" />