The first time I was replacing as oil pump gasket on a 1993 Villager, I left the dipstick in the dipstick tube. I got the whole thing back together. This is a pretty time consuming job. I an apprentice and it took me ALL day. I put oil in it and then went to pull the dipstick out. The damn thing was stuck. I ended up breaking the dipstick, while trying to pull it out. There is a baffle in the pan that caused the fully installed dipstick to bend in a 90 degree angle and it will NEVER come out like that. It took me another day to fix that mistake. I was paid hourly at the time so I got paid, but it was still VERY aggravating.
I never leave a dipstick in an engine like that. Also, when I take things apart I lay the parts out in order. For example, when I remove a front cover from an engine, I put the trigger wheel on the inside of the front cover.