A cautionary tale. Some (many) years ago, a new mill was delivered to Molins, St Mary Cray. The foreman stated that /no-one/ but he was to use it until he had thoroughly tested it. On the very first day, he succeeded in milling right into the bed.
I therefore /strongly/ recommend that Mrs Garp be invited to test-launch the new oven, and that Garp Snr put nothing near it until herself has managed to mark it in some way ...
** Phil.