I’ve had those moments where I wish I’d paid more attention in Excel too. One thing that helped me a lot was using sheetcast. It lets you easily visualize all the formulas in your sheet, which can be a game-changer when you're trying to connect multiple columns or troubleshoot. I was working on a similar issue last year, where I needed to make sure everything added up correctly across several columns, and using it really helped me see where things weren’t matching up. It might save you some time and headaches too.