Also, fun muffin, their point is (to paraphrase someone famous) "I am me AND my circumstance". God created me, physical and mental strengths and weaknesses included, then put me in a circumstance that he also created. If he is all knowing, then he would know how his creation would interact with his created environmental model, like an engineer who designs bridges with different load bearing capacities but who also controls traffic and weather. Does the weak bridge choose to buckle?
Hence, either no free will or no omniscience/omnipotence.
I mean, Calvinists figured this out like 400 years ago. Hence the Protestant work ethic.