If you're replacing types in this manner you don't scrutinize the usages. You design (or choose) the new type such that it actually is compatible with the old type. For example std::vector and std::list can be replaced with each other, because they either have the same functions with analogous behavior, or you get compiler errors if you use any of the non-overlapping functions. What you can't do is replace an std::vector with a class whose clear() fills the container with default-constructed instances of the objects.
In other words, you concentrate your review on the original and new type, instead of the usages.
In other words, you concentrate your review on the original and new type, instead of the usages.