You know me - black is black and white is white and there's nothing in between.
So what did you really mean, as I'm sure you know that statement isn't really true (as written). Maybe the key word is "warnings", but are you applying that to when the affected record count is zero?
EDIT: I might have to retract that statement. According to my understanding, dbfailonerror is supposed to generate a run time error if the record to be affected cannot be updated/deleted.
Even with the option selected (to be warned) and using CurrentDb.Execute with dbfailonerror, I'm not getting warned even with the target field in the target table being locked because it's being edited. Yet M$ says
The record locking option is set to "edited record", yet no warning. So none of my testing makes any sense.
I figured for sure, regardless of the setting you mentioned, warnings would be given if Execute failed with dbfailonerror and an attempt was made to alter a locked record, yet I can't seem to raise an error in any case. I do get the warning about someone else editing the record, but that's not what I was expecting.