Hi Steve,
Like when you open a bottle of fizzy drink, the gases absorbed in the fuel will form bubbles in the liquid as an aircraft climbs into lower pressure air. The tank pumps repressurise the fuel and deliver it to the engine fuel pumps in a gasless state.
When gravity feeding, this repressurisation will not occur and the engine pumps could ingest air as well as fuel which could cause fuel pressure fluctuations into the engine.
Hence the maximum gravity feed altitude, and the time delay to allow the fuel to deaerate.
PS, don't apologise for being an engineer. We need you guys !