Claudia Buengen wrote:

The "o" sound as in "Bob" does exist in German (at least if you think of

Actually, this depends a lot on where the English speaker lives. (Yes, I
snipped that part of your post.) I tend to believe that the
pronounciation of an upperclass Englishman usually slightly differs from
that of an Australian outback farmer. But both will have a very hard
time to to pronounce "Grob" as it is done by Germans.

(Shall we start to discuss how to correctly pronounce the "r"?)

Stefan