Last week I posted part one of Second Eyes (https://www.skool.com/cliefnotes/i-expected-a-second-ai-from-another-company-to-catch-more-it-caught-less?p=4179abfc. Quick recap... I planted 288 mistakes in 12 renovation cost estimates and had Claude, ChatGPT and Gemini review them in the browser, 180 reviews in all. A second AI from a different company didn't catch more than a second Claude. Two Claude reviews caught 84%, and Claude plus another company caught about 82%. A few of you asked the obvious next question. What about the tools people actually use? So I tested mine. WHY THIS ONE My everyday setup is Claude Code for the work and Perplexity as my second set of eyes. Claude Code is the version of Claude that can write and run code, so it can recompute every number instead of reading it. Perplexity picks the model for you and can search the web. If any setup was going to beat "ask Claude twice," I figured it would be this one. WHAT I DID Same 12 sheets, same 288 mistakes, same prompt and answer key as part one. Claude Code reviewed every sheet 5 times with all my personal settings switched off. Perplexity reviewed every sheet 5 times in incognito on its "Best" setting. That's 120 reviews, all on the same day. Before any data came in, I wrote down what would count as a win. Perplexity as the second look had to catch at least 5 points more than a second Claude Code review. WHAT CAME BACK Claude Code plus Perplexity caught 83.8% of the mistakes. Claude Code plus Claude Code caught 83.2%. Half a point. The 5-point gain is ruled out. On its own, Perplexity caught about 72% and Claude Code about 77%. And Claude Code caught about the same as the regular Claude chat from part one, 77% against 79%, even though it ran Python on every single sheet. The part I found most interesting... Perplexity and Claude miss different things. Perplexity was better at catching work done in the wrong order. It was much worse at catching numbers that contradict each other across the sheet, and claims that weren't true. But when I paired them, those differences mostly cancelled out. A second Claude Code review picked up about as many new mistakes as Perplexity did.