I have a parker 45 fitted with an extra fine nib. While I was at work it rolled off my knee onto the floor, I am now starting to question whether its a rule that the rarer a nib is the more likely something is to go wrong as I've placed my TWSBI down in exactly the same way more time than I can count and it's never moved. The nib shifted slightly but with very gentle pressure from my thumbnail, it went back into place. Luckily I had brought my other 45 nibs into work with me to give them a dunk into some gold cleaner so I had something to compare it to. Even before I put it back into place i