what is the 'bastardisation of oatmeal'..?

Barry called Zeminky the other day.. and between bursts of traded abuse, Zeminky boasted of his prowess as a drunk.

Barry dazzled him with his knowledge of the magic potion that creates the brotherhood of man.

"Minky", he said, "did you know that Vermouth is a bastardisation of the 'wormwood'..?"

Minky did not know.

"Aaaargh" he shouted in retort.. "be that as it may, YOU are the BASTARDISATION OF OATMEAL.."

This parable tells you nothing. But it does solve that mystery for me.

The only phrase more baffling is the 'pompatus of love'..

Did Minky inspire Steve Miller? And what the fuck is a pompatus? Answers on a postcard please.