Ok to make it simple:
When you fly to an area with a lot of critical terrain you have to check that you will fulfill the approach climb gradient with your landing weight at destination. In a cat 1 scenario it would be 2.1%. If you can't you have to do something to get the bird legal to destination. If the go around climb gradient is higher than what you can fly you have to fly you can fly the eosid.
Stop I don't get it. So in Zurich you need about 5%. You have to check the se ga climb gradient before you fly there? Is the approach climb gradient just a certification thing? Confusing guys