Contractual core duties abstractly are such duties whose accomplishment enables proper fulfillment of the contract in the first place and whose fulfillment a contractual party regularly may rely on. (https://worldofwarships.asia/en/content/santa2017/)
This whole sentence is hard to understand, especially "regularly may rely on" and "whose fulfillment" part. I am not looking for a professional legal advice. I just want to know what this sentence means (how normal audience would understand). Does this sentence mean:
Abstractly, contractual core duties is the duties that firstly enables proper fulfillment of the contract by accomplishing the duties, and the fulfillment of contract means that a contractual party may regularly depend on.