Well, I do not know any better.

I have no problem reading/hearing/respecting (in awe, usually) these more sophisticated (and, possibly/probably, more accurate techniques).

However, I still use a "modified" "timing using engine vacuum" technique
on my Stovebolt engines. The modification is described in step 6.

Saves time and saves equipment cost.
No need for an electrical outlet or battery.
The same vacuum gauge (and same connection) is used to quickly/easily set carburetor mixture.

My 235/261 engines seem to start easily and run like tops.

It is, however, good to know how the pros do it.