@jeffreybrown
That was the exact thing I was hoping to avoid. For the sake of tidiness, I don't want to create superfluous sheets like this, even if they can be hidden and kept out of the way, because my formulas rely on strict, self-explanatory naming conventions in order to be user-friendly for both Excel novices and experts. I'm almost more interested in why this behaviour occurs in the first place as there are many obvious workarounds but I'd like to keep the solution direct.
@popipipo
As for the single quotes, Excel is accounting for those automatically with copied sheets without me manually adjusting the formulas. If Sheet2 and Sheet3 are copied, the A2 cell will then reflect "5" for totaling the five worksheets. The issue is simply when Sheet1 is copied the sum formula worksheet references are completely destroyed for reasons I don't understand.
Thanks for your responses.
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