A guy in line at the hardware store told me he uses a 4-foot level for his posts

I was picking up some concrete bags in Tacoma last week and this older guy behind me saw my work shirt. He said he's been setting posts for 30 years and only uses a 4-foot level, never a 2-footer. He claimed the extra length catches the lean better over the full height of the post before the concrete sets. I tried it on a job yesterday with six 8-foot cedar posts and it did seem to save a bit of time on the back-check. Anyone else use a longer level for this, or is it just his personal quirk?