http://en.wikipedia.org/tools/~dschwen/wikiminiatlas/label/en_0_0_0 would fetch the content of http://tools.wikimedia.de/~dschwen/wikiminiatlas/label/en_0_0_0)?
Under NO circumstances will we ever do this, that's a serious security danger.
I fail to see how it would be a danger with a carefully selected set of forwards. We already have to trust the contributing admin users. Why would you categorically deny trust to another group of active developers: on the toolserver? Face it, security is ultimately built on trust in the users implementing it.