>>13564993 They're said to be super geniuses but I'm a dunce and I could have thought up most of their plans.
1. I doubt this.
2. It's not just their plans, but also their deductions of the opponent's moves, the thoroughness of their reasoning, and how quickly they can formulate them. In Light's case, it's also about being able to work both sides impromptu without tripping up. He had to, on the fly,
a) Be helpful enough initially for L to let him in on the case, then
b) Continue to be helpful to a degree that satisfied L's own reasoning, all while
c) Avoiding self-incrimination, and
d) Still leaving himself enough wiggle room to work.