The most practical solution here is to stop fighting the spreadsheet's structure and start working with it directly. The user has already built a series of IF functions and helper columns that technically produce the right answer, but the result is brittle, hard to read, and nearly impossible to maintain. That's not a failure of effort, it's a signal that the approach needs to change. When a data layout prioritizes visual matching to a paper form over analytical clarity, the spreadsheet becomes a display tool first and a calculation tool second. That trade-off is common, but it doesn't have to be permanent.
What matters most is the core insight: the total hours on task is simply the maximum time minus the minimum time across a row, regardless of which column holds the start. The user already identified this. The challenge is that Excel Online's built-in MIN and MAX functions work on columns, not on rows of mixed content. The elegant fix is to use a single array formula, something like `=MAX(Start:T8)-MIN(Start:T8)` entered with Ctrl+Shift+Enter in desktop Excel. In Excel Online, the same logic works with `=MAX(Start:T8)-MIN(Start:T8)` as a regular formula because the online version handles array operations natively in many cases. This replaces a dozen helper columns with one cell per row. It's not just shorter; it's self-documenting. Anyone who reads that formula immediately understands the intent: find the spread, subtract the earliest from the latest.
The deeper lesson here is about trusting the tool to handle inconsistency without forcing the data into a rigid mold. Spreadsheet users often over-engineer workarounds because they assume the software needs perfect columns to calculate. But when the data is structured for human readability, like this paper-form mimic, the smartest formulas are the ones that accept the mess and work with it. The user's instinct to "take the columns and make an array" was exactly right. That's the moment where a spreadsheet stops being a clumsy digital photocopy of paper and starts being a genuine analytical tool.
For anyone facing a similar problem, the takeaway is straightforward: identify the single calculation that solves your question, then find the simplest function that performs it across the whole row. If that function is MIN and MAX, use them. If you need to ignore blanks, wrap them in IF or use AGGREGATE. The goal is not to make the spreadsheet look tidy, it's to make the formula express the question directly. Once you have that, you can copy it down a thousand rows without touching a single helper column. That's the difference between a spreadsheet that fights you and one that works for you.