Something like stealth tactics is pretty easy to apply even without years of training. But combat tactics aren't something you can just pick up through reading and videos. You can have the knowledge and attempt to apply them but it's really all just like having hypotheses about what [i]could[/i] happen. 

After re-reading the CS, I guess as long as we're clear that he's not Solid Snake or Sam Fisher and still has a ways to go before becoming pro, then I can accept him. Anything more than that and there would be no point in knocking over a check cashing outlet if we could just send him in at night to do it.