I’ve been reading the thread on the Nasa spaceflight forum. The pad on which the launch ring sat was flat concrete — no flame diverter or water flood system. The hot fast exhaust did a number on that, and flying chunks of concrete precipitated several failures, including both hydraulic pressure units failing in flight. Without hydraulics, no more steering, and right after the big flame near the two-minute mark (a wet burp of hydraulic fluid into the jet?) the rocket started into plainly unguided flight.
The Mollusk wagered that since the pad stood a brief static fire at 50% power, it would hold up under a full-power launch. It practically exploded … some very big splashes in the water hundreds of yards away. So the operational end of the device took shrapnel. It is amazing it worked as well and as long as it did.
One wag noted that they had a reusable rocket, and an expendable pad.