>>And of course one needs to carefully read the documentation. While we might be aware of when we delete rows/elements in an array and all the trailing items are "shifted," the same does NOT occur when you delete a column in a 2-dimensional array.
>>https://docs.microsoft.com/en-us/previous-versions/visualstudio/foxpro/b26a3deh%28v%3dvs.71%29
>>in the Remarks: "... If you delete a column, values of the elements in the deleted column are set to False (.F.), but trailing elements are not moved."
>>
>>Update: just tried out quick experiment
>>

dimension afoo[3,3]
>>afoo[1]="one"
>>afoo[2]="two"
>>afoo[3]="three"
>>afoo[4]="four"
>>afoo[5]="five"
>>afoo[6]="six"
>>afoo[7]="seven"
>>afoo[8]="eight"
>>afoo[9]="nine"
>>display variable afoo
>>list memory like afoo
>>? ains(afoo,2,2)
>>list memory like afoo
>>? adel(afoo,2,2)
>>list memory like afoo
>>

>>
>>the results do seem to indicate that when you use ADEL() to delete a column, the trailing elements of each row *are* shifted.
>
>Ha! So they are shifted but, ahem, horizontally. Well, in these 20 years with Fox, never tried that - good to know what it does.

Of course reDIMENSION of an array where you change the number of columns could still throw you a curve if you're expecting columns to be inserted/deleted automatically.