I do this kind of stuff all the time (guesstimate or back-of-the-envelope a value for every number relevant to a hypothetical, then smoosh 'em together to come

I do this kind of stuff all the time (guesstimate or back-of-the-envelope a value for every number relevant to a hypothetical, then smoosh 'em together to come up with a thumb suck value to sanity-check an idea.) It's great, and the comparison to dimensional analysis is spot on.