Today, we know that proxigean tides do not cause erosion, but they can be the best predictors of erosion events.
A storm that occurs during a full moon proxigean tide can cause a great deal of damage, but if that same storm occurs only seven days later during a non-proxigean half moon, it causes considerably less erosion because the high tide might be lower by a foot or more.
During a month without proxigean tides, there might only be five days out of a single month when the tides go over 11 feet. But if a proxigean tide occurs during the same month a few years later, there might be as many as 20 days when the tides go over 11 feet—four times as many days when a storm can cause extreme erosion. During an average New England winter you might be able to squeeze by without having a storm during a five-day period, but you are almost guaranteed to have one during a 20-day period.