I finally got a go with a collection of many different tinders, a couple of hours, and a dry afternoon. I was on the quest for the perfect tinder. However, I soon stopped timing as getting a flame in any time was the main challenge. Roll on long, hot, dry summer days!
I used some punky rotten wood as coals for this experiment.
What did work time after time was something fibrous, and well rubbed, enclosed by newspaper (a substitute for birch or maple paper barks). I was hoping for something that gave flame in a couple of quick blows. But, I found I needed a good volume of slowly produced hot glowing fibres, not too loose and not too dense that seemed only possible with at least 6 controlled, not too forceful breaths.
Cedar bark, poplar inner bark (both of black and a locally growing different species), lime inner bark, clematis bark, grass, birch leaves, leylandii leaves were among many that did tolerably well, getting to flame in a few blows. (My lime bark was drier this time). But, nothing really stood out and nothing seemed to look like success in under 30 seconds was on the cards.
I think I will have a go at some charred material in a paper bark "cigar" next chance I get. Charred fibrous inner bark is my plan. I know lime bark is a good char and I suspect that poplar and cedar will be too.
I found reed mace interesting - 2 different parts. A) The seed heads would be fantastic to spread a tiny flame, but are not good in taking glow to flame. B) the leaves - light and hollow - if lit would burn very easily.
Got to get back out and collect some more material.