I have heard of it happening once or twice in the past. But I’ve always considered Lee molds to be somewhat disposable. Though I’ve never had to do this with iron or brass molds. They seem to have a nicer rhythm to them. Though I have seen Lyman molds in the past that were warped. Presumably some time after a very long life since they appeared well used. Who knows, a damn towel isn’t going to wick too much away. And I’ve done it without any noticeable harm.