Hairyplane, Fracturelines is likely PPL working on his CPL/CFI. Never mentioned being owner. Flying something ain't the same.
True, about the unusable fuel. Sounds more like rough guide for min fuel to have left when landing back/at the end of flight on VFR flight. Look at some generic POH and compare it with yours. If it's updated correctly, the main difference would be obviously W&B specifics.
FL, you were right about the seemingly inconsistent 80kts VNE. Seriously low.
No need to point out flight schools etc, but having placards for pop out floats and actually having fixed ones, is just shoddy standards, if not against A&P's safety standards. It is entirely possible the frame had pop out floats and then it got changed. Why not sort the POH and placards? Actually, I do believe it's against the rules. Ramp check may not be a pleasant thing if it happens and docs are as they are.