That Walmart parking lot jumper cable guy is a universal experience, @blairm35, like finding a dead alternator at the worst possible time.

Had a similar mess a few years back when my wood stove decided to belch a cloud of smoke right onto my living room ceiling. Spent a whole weekend scrubbing with a dry sponge and ended up just painting over the whole thing. Sometimes you gotta accept that the black ring becomes part of the decor.

Your neighbor was right about the node thing, but you actually could get growth from a single leaf if you had cut a sliver of the stem with it. The roots you grew are fine for keeping the leaf alive longer, but without that little piece of stem tissue and a dormant bud, the plant has no way to start a growth tip. That's why people who propagate figs swear by taking stem cuttings with at least one node above the soil line. The roots you grew are basically just there to support the leaf's life, not to build a whole new plant. So that root ball is just a fancy life support system for a single leaf that will eventually give up when it gets old enough.

Honestly though the tape trick is solid and way easier than measuring every time. It's one of those things where you wonder why you didn't think of it sooner. Saves you from wrecking a slide on the first screw.

My 1980s Nikon sat in a hot car trunk for years with a foam light seal that outgassed like crazy and never fogged a single frame. Unless you're sealing the foam inside the lens cavity itself, the amount of gas from a craft foam sliver is negligible compared to just dust and humidity.