I don't remember doing one, but I can't tell you for sure. I always taste for diacetyl whatever kind of lager yeast I'm using, and if I feel any "slickness" in the sample by tasting it, then I do one. I do one about 1/2 the time- but I always pitch a big big starter and always pitch cold. I think that often is what negates the need for a diacetyl rest.
Broken Leg Brewery
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