In most cases there's really no such thing as "leaving a beer in secondary too long." The purpose of a secondary is to bulk condition/clear. Depending on the gravity beer's can be left in secondary for years. For example I have a 17% abv barleywine that sat in secondary for close to 2 years and is now in an oak barrel. It won't even be consumed for another 2.5 years.
You'll find that often the longer you condition beers, the better they will be. Especially higher gravity ones, and things like Pumpkin beers with a lot of stuff going on, that you want the flavors to come together.
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Revvy's one of the cool reverends. He has a Harley and a t-shirt that says on the back "If you can read this, the bitch was Raptured. - Madman
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