Directionally Challenged (Meta)

There are times when a meta idea occurs to me and I think, "Can I do that?" For this puzzle, though, the operative question is, "Should I do that?" You may decide I was wrong to proceed; you may question my sanity; you may even question your own before you reach the end of the grid. But please don't 42 down! If you persevere you will find yourself in a position to solve the meta, the answer to which is something that, unlike this puzzle, cannot be reversed. However, if you would prefer a less challenging grid (but with a slightly harder meta), then click on over to "Directionally Unchallenged" (https://crosshare.org/crosswords/yKMjrhD9wX4y9A7dvTwu/directionally-challenged-meta). Answer & explanation: https://www.xword-muggles.com/viewtopic.php?p=140859#p140859

Check out "The MOAT Mini Pack of Marching Bands" here: https://www.ephesusscroll.com/about/interest4.html. US$5 gets you 7 Marching Bands which, hard enough on their own, now contain metas too. And once again there's a mega-meta!