Shore was regarded as a very good defensive player, but he wasn't the best in his era. Lidstrom was almost certainly the best defensive blueliner over the past fifteen years (Pronger too inconsistent and undisciplined, and Stevens playing for only half that span). To quote myself from another thread:
Eddie Shore was not even regarded as the best defensive player of his era. Although he was known as a good offensive player, even during his absolute peak (1933), contemporaries thought that there were several other defensemen in the league who were superior defensively (ie King Clancy, Lionel Hitchman, Ching Johnson). Source: Globe & Mail, April 20, 1933.
I don't want to put too much stock into a single quote from a newspaper, but I place emphasis on it because it's:
1) the opinion of someone who actually watched him play (as opposed to a book written years or decades later, which tends to include a lot of praise and very little criticism of any player)
2) it's in the middle of his first Hart year (so it's not like I'm cherry-picking a negative quote from before or after his prime)
3) he was already established as a star (so it's likely that the journalist would be fairly familiar with Shore's strengths and weaknesses)
Offensively, if you remove the 1940 season (Shore was 37 and played just 14 games), we get the following:
Player|Games|Points
Eddie Shore|536|276
King Clancy|456|219
Lionel Conacher|465|172
Georges Mantha|440|170
Hap Day|519|164
I've removed Baldy Nortcott, who played both D and LW. From what I can tell he was primarily a forward:
1) he broke into the NHL on a scoring line with Ward and Trottier (
link)
2) he was the first-team all-star LW in 1933 (his only year as an all-star)
3) he was described as "a big scrappy winger who also saw some action on defense" (
link)
I don't know exactly how many games he played as a forward, but it sounds like it was at least half - so he's not a fair comparable to Shore.
This means that Shore was the highest-scoring defenseman of his era by a 26% margin, and over 60% ahead of third place.
In fairness to Lidstrom, he had a higher margin over second place, maintained his margin over a longer period of time, and over a larger talent pool.
I think that a lot of people rank Shore's offense highly because he was an offensive catalyst (initiating plays, rushing up the ice, etc.) to a greater extent than all but a few defensemen in history.
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I've argued at length that Harvey was superior to Shore in every conceivable way (aside from Hart trophies and evilness). I don't think it's fair to dismiss all the people who watched Shore who said that he was, at worst, the second best player of his era, but it doesn't hurt to reconsider our rankings.