I think the key to this one are the settings in

Tools -- Options -- Calculation...

And the tick-boxes
- "Update remote references" and
- "Save external link values".

As I understand it, a workbook that doesn't have the latter one ticked is forced to read the values from the external link, regardless of whether 'Update' or 'Don't Update' is selected.

Whether you are asked the question about whether you want to Update or not doesn't depend on the setting of the latter, but on the former (i.e. "Update remote references").

If you untick this one, the question won't get asked, but if "Save external link values" is left unticked you would then get no value at all in the remotely-linked cells. So your Johnny and Bob may read #VALUE or #NAME or #REF.

In short, the answer would appear to be, untick "Update"... and tick "Save external..." on BOTH worksheets.

NOTE: Even though these settings are in Tools -- Options, they are WORKBOOK-SPECIFIC, not Application-specific

BizMark