As somebody who is not an american, why would it be cheaper to get a health insurance through work if I had a preexisting condition - other than the obvious tax savings?
Your individual pre-existing condition does not bubble up to the group. However, when negotiating as an individual, then each pre-existing condition does get considered and factored into the cost. There's power in groups.
Well, in most situation yes. You as an individual. There other problem with pre-condition, it's very broad. They can make up all kinds of BS and claim your application must be filed different because of some "magical" precondition.