Oh good grief, I am not sure I really needed that reminder.
I was visiting a friend a few years back and got drafted to solder up a simple cable to finish servicing his car, a cable that had a couple 2.5mm diameter automotive contacts on it. I used one of those irons for the job because that is all he had. The tip was at least five times wider than, well, necessary but somehow I managed.
When I asked about a heat gun for the heat shrink, he said he did not have one. So I let him set the shrink with a couple matches.