There's not really any decision making in solving the cube when you have learned the method, you just see the pattern and execute the algorithm. That doesn't really change at all with the inspection time.
The inspection phase is not really about "solving" the cube, but more about checking what is the best route to start solving the cube. In the most commonly used solving method that means that they are checking which color to create the initial cross to and what corners to place in first. If you take out the inspection phase, they will more or less just have to choose that at random, which will only cause more random variation to the final times which is already a huge problem with single solves.
Also comparing current record times by including the inspection time is absolutely useless, as the optimal way has been to use as much of the 15s you have to make sure that you are choosing the right approach and the time used for the inspection has no correlation to the time they have actually needed to inspect the cube.
The "oh shit" move doesn't necessarily make your position suddenly way worse, it can be just the moment when you realize how much better your opponents position has been for a while.
Maybe, but not really. The challenge in this game comes mostly from arbitrary line count limitations between imaginary "nodes" and their connections. You are writing some thing very close to assembly, but the problems you'll face are mostly unique to this game. It's terrific fun so you should definetly pick it up though!