Calculation loading is complex because different calculations can
depend on differently parameterized things. FOr example:
```elixir
def load(_, _, _), do: [foo: %{arg: 1}]
def load(_, _, _), do: [foo: %{arg: 2}]
```
The previous naive implementation would simply merge all of the calculation loads, which naturally would not work. Now we ensure that we load each requirement in isolation.
