^It's a fantastic attraction, I was so pleasantly surprised.
As far as capacity goes, they might need to tweak that unless they don't mind serious waits. Perhaps have a group in the first room while another group is going through, and see if they can squeeze six into a group, or at least to make an effort get five in a group. Last time I was there, if there was 3 in a group they didn't bother trying to find a pair (they only did this if there was 2 on their own going in).
This is a great example of a small addition that can add enormous value to the experience at the park.