Curd it is

When Rico is wrong, he (if reluctantly) admits it:

Rico says he loathes shoddy work, and bad proofreading is high on his list.
Having been rewatching (and thoroughly enjoying) Smiley's People (with the inestimal Alec Guinness as George Smiley), he has been repeatedly irritated by the spelling of one of the (well-known, too) actor's names.
It is not Curd Jergens, but Curt.
Stupid and unforgivable...

Rico's friend Kelley quickly squared him away:

Calm yourself, Rico. "Curd" is his birth name. It was changed when he made films for an English-speaking audience:

"Curd Jürgens (photo), commonly billed as Curt Jurgens in anglophone countries, was one of the most successful European film actors of the Twentieth Century. He was born Curd Gustav Andreas Gottlieb Franz Jürgens on 13 December 1915, in Solln, Bavaria, then in Hohenzollern Imperial Germany, a subject of Kaiser Wilhelm II."

Rico says okay, but it's still a stupid name...