Oil flush

Some of you may think I'm not playing with a full deck but bicycle restoration requires some lateral thought. I am attempting to resuscitate a second Auto-Mini bicycle where the bottom bracket (BB) was not turning freely. I'm fairly certain the bottom bracket hadn't been lubed in decades.
I tried some drops of oil down the seatpost from my $10 bottle of oil from my LBS (Local Bicycle Store) which brought about some improvement. I then thought if some is good more is better. So I bought a litre of 30W non-detergent oil in Walmart for $4. The oil container says "Recommended for use in hydraulics, light-duty gear boxes, general oiling and pre-1940 engines."
I poured a quarter of it down the seat tube, letting it run out the bottom bracket. It ran through fairly rapidly dislodging some crud on the way. The cranks are now turning freely.
For those of you who thought you should use grease I can only quote Sheldon Brown: "The difference between oil and grease is mostly a difference of degree. Grease is very thick oil; oil is very thin grease." I am old enough to remember that my first bicycle, a Raleigh, had an oil port on the bottom bracket. Anyway stripping the BB, wrestling with cotter pins, and possibly damaging it in the process is not for me. I shall investigate fitting an oil or grease port later.
I wondered if this bush mechanics trick had been tried before and found somewhere on the internet where olive oil had been used to silence a noisy bottom bracket in similar fashion.
Pic by RLT.