You need to remember that most ale was drunk by the working classes, and in fairly large quantities. Rehydration and refreshment were the key objectives, and once you get much over about 4% it gets difficult to re-wheel a wagon or thatch a roof. The Pilsner invasion has caused its share of problems as the louts adjusted to a higher alcohol content. I used to get plastered when I first came to Oz, drinking all this tasteless icy cold liquid at 5% or more, at the same pace I used to drink pints of ale. Come to think of it, I often got plastered on ale too...