I'm not sure I would after brown sauce either :D :D seriously tho I haven't eaten brown sauce since, if it digests the dirt off a penny......

Cillit Bang (what a name!! :D ) appears to clean anything except enamel baths and marble, from this I assume its an acid of some kind, in my soft water area things usually clean up easily and if they don't there's always Brown Sauce :D :D :D :D :D