I feel like I've just walked in on an episode of 'allo 'allo.
(For those not in the know, it was a british comedy set in Nazi occupied France during the second world war. In this show they used atrocious accents for comedy effect. It is however very dated and old. What I'm insinuating here is that Stiff's usage of either street slang crossed with a literal usage of a German accent is both annoying, old and makes him look a bit retarded)