I know, I asked dang to fix it but he refused. I'll have to live with it I guess.
What I like about your project is that I've always felt that debuggers and such give us the same 'von Neumann' view of running programmers that we feel our CPU has. It's a bit like trying to figure out why your car won't start when all you have is a view through a microscope. And besides that, it is quite often that which is not happening that is indicative of an issue and debuggers usually allow you to focus only very well on everything that does happen.
Maybe you feel that way because that's exactly what debugger was designed for: CPU register access in assembler programs..
It's pretty insane that every other aspect of software engineering has changed so dramatically since the 1970s, but debugger has remained fundamentally unchanged for almost half a century now.
Also.. next BugJail beta will have SQL queries against captured program execution (select * from field_write join method_call...) to test hypothesis about runtime behavior. If you can express "that which is not happening" in SQL and get back 0 rows, then it didn't happen. Do you think this could solve your need?
Btw you have a bug in your HN profile, it shows "Karma 158422", which seems to be about two orders of magnitude off? ;)