'Not so clever', old Beatty said to employer (7)
I believe the answer is:
obtuser
'not so clever' is the definition.
I can't judge whether this defines the answer.
'old beatty said to employer' is the wordplay.
I cannot quite understand how this works, but
'old' could be 'o' (common abbreviation eg in OE for Old English) and 'o' is located in the answer.
'employer' could be 'user' (someone who employs or uses something) and 'user' is found within the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for obtuser that I've seen before include "More insensitive" , "Comparatively stupid" , "More dull" , "More dumb" .)