FBO's black HEI ignition box

That’s exactly why you have to test for it. You might be surprised that most NA cars want MORE timing in low gear, “standard” timing through the middle and MORE timing again in high gear.

It depends largely on load and VE in high gear

If you don’t know when an ignition starts to retard and when it retards then you have no idea what you actually have for timing.

I used to advocate for (and did it all the time) locked out advance on most any performance build.

Once I learned about ignition retard is STOPPED doing that and build some kind of curve for everything.
Yup and another thing, engine A built a certain way will want different timing than engine B built the same way. Every dang time. It's just not something that's set in stone. You have to tune for it.