If you allow Pathagoras to create your ‘date’ and ‘name’ Content Controls, and if you are using arguments (dates: (ext), (long), (num4), etc; names: (first), (last) ), you can change the one ‘parent’ variable/value paring and the CC will update all the other fields appropriately. Even Words native CCs cannot do that.
When originally created by Pathagoras, these arguments are actually embedded in the Content Control. (They are part of the 'tag' element, for those familiar with the structure of Content Controls.) Even though the 'Title' to the Control is the parent variable (e.g., [Client Name] is the parent variable for [Client Name(first)] and [Client Name(last)]), Pathagoras knows to replace just the first or last name, as appropriate and in the appropriate spot. Same with the various date variables.
You can change the variables 'globally' (i.e., recall a record, but change only a single variable, perhaps to correct a misspelling of a name or location). But you can also change a single variable (perhaps the date of signing to reflect a new date). If you want to change a single variable, just click inside the variable and press Alt-D. A regular IDB screen will appear, but just a single variable (the one your cursor indicated) will display. Make the appropriate change. Press 'Next>>' and the change will occur throughout the document (with arguments which are now part of the Content Control being honored). Please note -- if you choose the latter method, there is no updating of an Instant Database record. Only the document is changed. If you need to update the record, display the Instant Database screen and recall the appropriate record. Make the change and save the record.