>>

>>SELECT alias
>>SCAN
>>

>>is helpless, if workarea is changed in between.
>> ¯\_(ツ)_/¯
>
>The last sentence is wrong, Scan will take care of changing the work area back to the correct one.

That's if the scan command is executed, then yes, it will.
If the change of workarea happens between select and scan... it will scan a wrong workarea (and break on the mention of a first nonexistent field) or break right on if no alias open in the current workarea.