It's ok. I purposely didn't say "good", "great", or "fantastic". Just ok.
The fact that he used double layer walls in his most inner wall is better than using them on the outer walls. I'll tell you why. Because double layer walls are still useful against non-wallbreaker troops. So if the attacker uses up all their wallbreakers to penetrate the outer walls, the inner double walls will still be effective in acting as two separate layers of walls they have to physically punch through (again, only if the attackers wall breakers are all used up or get shot down en route and don't reach the inner layer double walls).

