I saw this documentary a couple of years ago. Unfortunately, at that time I had no way to capture it for future reference. I wish this clip began about a minute earlier so it would show how carefully he set himself up for the initial lighting. He carefully places the match in his right fingers, strikes it, then tucks the matchbox in among the fingers of his left hand. This seemed an awkward ritual to me, and I wondered: why didn't he just put the matchbox down?
I thought about it, and I decided a plausible theory was that this was a habit he developed during World War I. He spent time in combat in France, and there probably wasn't a good place to put a matchbox down in the trenches. Another thing that strikes me is how me makes that first match count. Does it look like he's going to need a second light? I must admit that when I use matches--as I always do when I'm home--it can easily take me three matches to get the thing going. Possibly another holdover from an earlier time when matches were a semi-precious commodity and he had to make sure every one counted.
Unfortunately, I can't remember the exact title, I think it may have been the one called A Film Portrait of J.R.R. Tolkien. At the time, it was airing on the Ovation cable channel. So keep an eye out for it, and if you get lucky enough to find it, you might get to see a more complete version of his pipe-lighting ritual.