I agree, for small not skill based clans like mine, your current application system is pretty useful, i don't want very skilled people, but i want people to put some effort into getting in. If you are looking for skilled players, testing ingame is the most effective way. Everyone can have a good day and save the replay, even if he isn't very skilled, so the replay idea is pretty ineffective.
And about testing ingame, you should create a rule like "every member from tier 3 or above has the right to test applicants"
This way you would have many people who can test them and there would be at least 1 "tester" online 24/7 bc of timezones and stuff.