They way I see it is that "milking" ends up running down the property you milk. Kinda like how a land becomes less fertile the more you use it for crops etc.
I don't think S-E milks but if I may take some other game, Tomb Raider then yes, I consider it milking. After the first two games, the value deluded. Number one was fresh, was great and number 2 perfected the standard of number one. After that, the tomb Raider lands got less and less fertile as the only upgrades where in the graphical deprtament.
Nintendo on the other hand keeps their lands fresh by adding, and having a quality standard. Mario Galaxy might be the last Mario adventure in a long line of mario adventures and people might consider it milking because of that.
Now let's say we put Crash Bandicoot or a new character in there, without 'tude... I'd say it would have still rated as high.
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