Ha ha ha very funny. Whoever told me that "hot swapping" Lamy nibs is easy to do . . . is a liar. I just pulled off the ridiculously scratchy and always-clogging EF nib from my Lamy Vista (with a converter full of dark blue-black ink), and exchanged it for an F. The "F" in this case stands for Fail. The adhesive tape trick didn't work so well due to the wet nib. I finally managed to yank the EF nib from the feed, but I almost lost it down the drain. Ink splattered all over the sink and my fingers got a nice dosing of blue-black.
I thought I'd be smart and use a tissue to hold the F nib during installation, but that resulted in a tissue fragment getting caught between the edge of the nib and the feed. So I had to remove the F nib, clean it off, and re-install it. Good times.