I sat down with Justin Brooke, a 20-year advertising veteran who turned a $60 Google Ads campaign into a seven-figure agency — and then built an AI-powered prediction system that has since generated $260,000 for him personally. In this episode, Justin walks through his "predictive wear" framework: a multi-agent workflow that runs your ad copy and sales pages through a synthetic focus group of 13 detailed AI personas before a single dollar is spent on ads. We break down how the workflow is built in Mind Studio, why persona quality makes or breaks accuracy, and how Harvard, Stanford, and the New York Times have all validated this exact approach. By the end of this episode, you'll understand why running your marketing through a virtual focus group before it goes out the door may be the single highest-ROI move you can make right now.Timestamps03:29 – What "predictive wear" is and why Justin built it05:00 – Why you need multiple personas, not just one08:00 – How the 13-persona focus group workflow runs09:00 – The prediction engine: picking the winning ad variation10:00 – Harvard, Stanford, and the New York Times validate the method13:15 – The ROI: $260K personally, 4 to 6X ROAS for clients19:00 – What makes a persona accurate: the 1,400-word dossier24:04 – The copywriter prompt and "embody" vs. "pretend to be"33:00 – Sales page version: PDF upload and yes/no buyer scoring41:00 – Why some personas are successful and others are struggling45:00 – A $36,000 offer launched using this exact process48:00 – Final advice: do the work on the persona qualityKey PointsThe old way of advertising is learning by spending money — you write copy, run ads, and find out if it works after the budget is gone. Justin's predictive wear system flips this by running copy through a synthetic focus group of 13 AI personas before any ad spend, so you know what will convert before you go live.Harvard, Stanford, and the New York Times have all independently validated this approach. The New York Times uses the same synthetic audience process to test headlines and found 92% accuracy compared to their human focus groups — meaning this is not a fringe experiment, it is becoming standard practice for major publishers and brands.The cost is 13 to 20 cents per run. A top 1% copywriter charges $100 to $500 per ad. Justin's workflow produces three optimized variations in about 10 minutes for 13 cents, performs at or near the level of the best human copywriters for most use cases, and allows unlimited iteration — you run it until the copy converts.The system is also a copywriting trainer. Even with 20 years of experience, Justin says the feedback regularly surfaces blind spots and teaches him better approaches. Anyone can use this, not just expert copywriters. Because the workflow takes whatever you input — even a bad ad — and improves it based on real persona feedback, non-copywriters like a front-desk employee or a local business owner can now produce top-10% ad copy without prior training.Join the Build With AI community built for non-technical entrepreneurs: https://www.skool.com/buildwithai/aboutIf this episode was valuable to you, it would mean a lot if you left a rating and review on Apple Podcasts or Spotify. It helps more entrepreneurs find the show.FIND ME ON SOCIALX/Twitter: https://x.com/coreyganimInstagram: https://www.instagram.com/coreyganim/LinkedIn: https://www.linkedin.com/in/coreyganim/YouTube: https://www.youtube.com/@coreyganimFIND JUSTIN ON SOCIALhttps://x.com/IMJustinBrookeWebsite: https://adskills.com