Genuine question, not sour grapes (fine, 20% sour grapes). We were Opening Prop and I thought we'd built the fairness case well. Closing Opposition won on what felt like one argument about selection effects. What did the judges see that I didn't?
I was on the panel — happy to give fuller feedback Thursday, but the short version: their selection-effects argument didn't just attack your fairness case, it explained your own evidence better than you did. That's the most dangerous kind of argument to concede.
Also they weighed relentlessly. Every rebuttal ended with 'and this matters more because'. You had better material for the first half; they told a better story about the whole debate.