Hi Claus,
We are a bit opposites in how we treat our carbon steel pans. I never season my De Buyer, and I scrub it clean every time after using it. I also just deglase in the pan with wine. Life is too short! 
It’s my favourite pan for high heat searing, closely followed by my 2.3mm stainless steel lined copper pan. Imho if one needs just one frying pan and you cook on gas, get the copper. Or second choice, gas and induction, the Paderno grand gourmet paella pan. Both are more versatile than the De Buyer. (And for me as for the Proline: never again…)
