You're assuming that the only thing firemen do is fight fires. There's also the extremely important role of search and rescue, and in an emergency one could imagine that firemen would carry that out even in the face of inadequate supplies of water. That will, of course, at times lead to the deaths of said firemen in the attempt to save the lives of others, which is why we tend to accord them an extraordinary measure of respect.
Dave
Interviews could reveal how many firemen were involved in search and rescue, how many of the rooms did they actually enter, were they in a position, location-wise and smoke-wise, to see CD implements if they were there, and undisguised, etc.
We have now had an 'official' BBC program on WTC 7, and what new knowledge was gained on this score?
Now that I think about it, wouldn't taking down a skyscraper in NYC make for a spectacular terrorist action? Of course, they'd want it to fall over, not come straight down. I find it hard to believe that counter terrorism people haven't addressed the question of how to conceal CD implements, which could be positioned over time, surreptitiously. Did BBC bother to ask counter terrorism people? Not even Jack Bauer?
I doubt that CT (counter terrorism) people would give out this information, but they might have been willing to give out yes/no type information as to it's plausibility. Was the BBC curious enough to ask them, or was Loizeaux the only expert they thought worth talking to? Loizeaux, of course, does not need to conceal his work.