But also if you know anything about engineering, it’s double your expected timeline just in case Shit Happens™️. I can fairly safely predict delivery in two hours. I might be able to deliver in one. Under-promise and over-deliver, or risk vice versa.
You’re old school, like me. You’re literally describing the “new math” that boomers hate. Teachers are finally teaching kids to do it the way we’ve always done it in our head.
“8 + 7 is awkward, but if you take two from seven and give it to eight, now you have 10 + 5 and that’s easy mental math.”