Opinion is divided between spreadsheet users who value Excel's ability to express formulas in terms of meaningful names, such as =Revenue-Costs, and others who prefer the traditional coordinate notation, such as =D5-D7.
When OAK's Formula | Reconstruct command encounters names in a formula that it is processing, it automatically removes the names and converts the formula into coordinate notation. The idea is that OAK should provide insight into the processing performed by a calculation, by re-expressing it as simply as possible.
This behaviour is particularly useful for checking one kind of error. The formula =Revenue-Costs is arguably easier to read than =D5-D7; but it will nevertheless give the wrong answer if Revenue or Costs have accidentally been defined so that they refer to the wrong cells. Reconstructing the calculation, and checking that the links that appear in the reconstruction report lead to the right place in the spreadsheet under test, is one way to verify that it is not undermined by misdefined names.
For example, in this spreadsheet the total costs is calculated as =CostsFixed+CostsVariable+CostsOverhead, where those three terms are names that purport to have been allocated to the relevant ranges above. But due to a fault, CostsOverhead has become associated with row 5, rather than row 6 as intended.
The fault is not at all apparent from inspecting the spreadsheet. Reconstructing the total makes it obvious: it shows only two rows 10 and 11, instead of the expected three, and the formula shows the double counting of row 11.
In this particular example, the fault could perhaps be seen if Excel is put into Edit mode (click on the formula, or press F2 while the cell is selected); then Excel highlights the cells involved in the calculation, and uses colors to link them to the relevant terms. But it takes particular concentration to notice that two rows are highlighted while one is not, and to see that the same colors are used for two of the formula terms. And in the case when the cells mentioned are on a different worksheet from the formula doing the mentioning, the precedent highlighting is no help at all.
Some auditors will prefer to check the name definitions systematically, one at a time. For those people, OAK offers the Build Names Database command.