There are the stories one hears about the all SS breweries in Germany, that have a section of Zinc piping.
As far as fermentation speed goes, my lager fermentation times now that I use nutrients, proper pitch rates and O2, are in the 5-6 day range, which is what the 2 German Brewers I talked to on the respective tours said they experience. Whenever I read of a Homebrewer doing a standard lager, and the fermentation has been going on for 2 weeks, well I try and help.