Niceday,-with the greatest personal respect.....bugger strictly speaking! Dont give the bloke nightmares he doesnt need!
If the light comes on,goes off very soon after pulling away and the brakes work safely,thats good enough for the MOT.As long as its safe....and the tester will tell him if its not,....then he can worry about the niceties when he's through the test.
Snoops,can you feel the ABS when you break HARD?If so,then really,dont worry.
Sorry niceday,nothing personal mate