Look at the plot that resulted in the three-way tie in the underwater Defense battle.

It only looks complicated. Yes, it was not extremely probable that Blaise would be amongst the last few standing. But very quickly all teams raced towards an even score in a fairly predictable self-organizing way. So there weren't really a lot of moving parts there, just one complicated system with fairly predictable behavior, and some complicated-looking plotting to get Blaise's cooperation, and just a bit of luck that Blaise didn't get knocked out earlier (helped by Blaise being mostly interested in survival instead of racking up points)