It's just that this is a pretty massive project, and I think it would be a lot more exciting to reveal it all at once at an event like this than to reveal it piece by piece along the way.
I have to say that I'm unmoved. Filesystem discoveries are of such basic utility to Lisa enthusiasts that big-presentation glory for one particular project (however famous) doesn't really justify keeping the secret in my book, at least not for a patch that I expect amounts to changing a single-digit number of bytes. (It will be interesting to know if that hypothesis is correct!) Other people may have other projects they want to accomplish on their machines, and in my own opinion it's better for everyone if they don't have to wait for such a fundamental enhancement.
I assume that patching the ProFile driver is a relatively small part of your efforts. If that's correct, and if wanting to "be there first" is part of your motivation, I wouldn't overestimate the number of people with the will and the patience to try and accomplish the "hard part", which is to build the Office System and its tools. Who knows, but I would expect that a lot of people have other designs on their free time between now and June.
But let's say that you did get scooped because someone else gets their hands on a big ProFile: the worst-case scenario! Maybe they will get some story-of-the-day fame on hackaday and hacker news or something. You're still the one who's going to show all your work to an excited crowd at VCF; you'll be filmed and people are going to be able to ask you questions and talk to you in person. You know the deep lore and the technical details, and your care to share your knowledge (eventually

You were not the first person to make a ProFile emulator, but ESProFile is now celebrated as one of the best and most accessible options out there, and rightly so. I expect the same outcome for your current project even if you aren't the first across the line. (Although I suspect you will be regardless.)
Big ProFile Technique is your discovery and so the knowledge is yours to do with as you wish, for now. But I may get a wild hair someday and try to figure it out for myself, and if I do, I will remain tempted to tell everyone how to do it. I'm still pretty busy, though. Maybe it's this evening that I'll finally get time to test those Monitor ProFile images...