I was thinking of PE, but he may be in a rather difficult situation, if he has, indeed, designed TF-5. He might want to keep his discoveries to himself, so as not to jeopardise the commercial success of TF-5, even if it seems, from his numerous, knowledgeable, and always very helpful posts, that he genuinely likes to share his wisdom. I just hope that this knowledge is not lost, for the future. It amazes me how much we used to know that we no longer do. When I met Neil Armstrong a few years ago, he remarked that he was sorry that we have already lost the knowledge, and the skill, how to get to the moon, even though this has been achieved numerous times a few decades ago. I realise that photochemistry is not in the same rank of importance, or difficulty, but it is a pity to lose valuable knowledge nonetheless.