Links to non-existent workbook magically work

[hawkes.trevor]

I have a workbook, workbook A, with lots of cells that link to a source workbook, workbook B. I copied workbook A from my hard drive at work to do some stuff at home, but I did not copy workbook B. I can't figure out how, but when I open workbook A (at home), the links to workbook B appear to be fine. I can change cell values in workbook A that affect other cell values which also depend on workbook B, and somehow the results appear to be normal. When I use the "Evaluate Formula" tool to step through the calculation steps, I get these results towards the end of the formula evaluation:

IF(FALSE,#N/A,VLOOKUP("sample text",'C:\Path_to_nonexistent_Workbook_B\[Workbook B.XLS]SHEET 1'!$A$1:$R:$10,6,FALSE)*B2)

IF(FALSE,#N/A,#REF!*B2)

IF(FALSE,#N/A,#REF!*1)

IF(FALSE,#N/A,#REF!)

82.729

I would love to understand what is going on here. Any ideas? Thanks in advance.