Yo that's such a real lesson to learn the hard way. People forget even plywood or MDF edges can suck up moisture and change size a tiny bit. Your tiny gap fix is smart, it's basically giving the wood permission to breathe without throwing a fit.
Hey @leo_lopez, but does that tiny bit of swelling actually mess anything up in practice? Most stuff is in climate controlled homes anyway, so the change has gotta be super small. Seems like worrying over maybe a credit card's thickness of movement, if that.