Because even with knowing the frame to hit, my success rate was around 15-30% for the general case; only shooting several in a row from the same setup was markedly easier. Without video it's going to be "can't repro" in no time. With a video the tester can at least see it happened (or see I'm just tripping), and know exactly what was done. There's plenty I won't be able to describe, and plenty I don't even know, some good evidence gathers a lot of that.
So you think a tester would only try this 2 times after you told him the success rate was about 10-30%? You have a low opinion of testers. On the other hand your repro steps were excellent work and it will be really hard for the testers to miss that now.
It's not mandatory, sure, but in this kind of case it's a lot more useful than the template they want you to fill...![]()
When you see the average quality of bug reports you know why they want people to fill out that template. The template is not really to get information about the bug but about the poster.