Um... yeah, I disagree. No cushioning is going to survive for 50 years, and something like an office chair should be rotated far sooner than that (or maintained

Um... yeah, I disagree. No cushioning is going to survive for 50 years, and something like an office chair should be rotated far sooner than that (or maintained with replacement cushioning/support) to keep the ergonomics intact. Especially for an office chair (assuming this is something like an 8-hr chair and not a short duration task chair).