OMG, just had a thought on the funny pattern on the stirrer stem. I presume you keep keep the stirrer on while slowly removing it like I do. Maybe it's just as simple as centrifugal force creating the odd pattern.
Dunno why I never thought of that.
Back to the strainer in the cap, one reason I decided to try it is this stuff dries so fast I theorized that having the cap off the stir and pipette-transfer probably causes drying around the mouth, and that has to fall somewhere. Though maybe best to keep the lid on.
OTOH, I hate the way the paint drips all over the bottle with the squirty cap.