how's this for a general rule. drydocks represent a percentage of an existing shipyard, deployed, at a cost. for example the mora shipyard has a 10,000,000 dton capacity. for that yard to build and support a 1,000,000 dton drydock reduces the mora shipyard capacity by x2, meaning now it has a planetary capacity of 8,000,000 dtons but may deploy a 1,000,000 dton drydock for work anywhere else. the drydock is for all intents and purposes part of the mora shipyard and follows all the rules thereof.