VaWaterfowler, it is true that using a full choke is not generally needed for steel shot, but it can be used with smaller shot if the situation permits.

This post is talking about pass shooting, a form of waterfowl hunting that most people never take part in. He is probably hunting a place that the birds would never land in, but only pass over. If they pass low enough it can provide some good shooting. Unfortunately, many of the shots generally are at near max range and the birds are moving quickly. That is why you need heavy shot and tight chokes to take birds consistently while pass shooting.