Then why not just use an airlock on the bucket? I did and still haven't got a straight answer on this. Some say the yeast needs air, but I don't really see how that little hole is going to give it any. So long as you are stirring it twice a day wouldn't using an air lock be just fine?
While on the subject, I only left about 2 or 3 inches of head space in the bucket and never had it foam out or anything using Champain yeast. Is it that the champain yeast doesn't foam as bad as others? If so, what yeasts do I need to watch out for foam from?