I've just had the timing chain changed recently and the car doesn't feel as spritely as it did, I'm wondering if the timing could be out?

I've spoke to the VXL dealership and they said there is no way the timing could be out as the car wouldn't run smoothly and emmisions would be all over the place, is this true, I thought the car would run perfectly smoothly if it was 1 tooth out, but just wouldn't perform as it should?

Thanks in advance