The yield numbers given by breeders typically mean that an expert with the best equipment and conditions can get that yield - and it's not per plant, it's generally per square meter. Some will say under a 600 watt hps - others will say 1000 - some don't say at all.

And that's usually wet - I like the breeders who say per seed & cured weight personally.

Use those numbers to say that one strain produces relatively higher than another rather than planning to get that much yourself - especially if you don't have a professional-grade set-up or you're inexperienced.