Traditional valuation models assume growth decays over time. However, when a company at scale, like Databricks, begins to reaccelerate, it defies these models. This rare phenomenon signals an expanding market or competitive advantage, justifying massive valuation premiums that seem disconnected from public comps.

Historically, US earnings outgrew the world by 1%. Post-GFC, this widened to 3%. Investors have extrapolated this recent, higher rate as the new normal, pushing the US CAPE ratio to nearly double that of non-US markets. This represents a historically extreme valuation based on a potentially temporary growth advantage.

Today's high S&P 500 valuation isn't a bubble. The market's composition has shifted from cyclical sectors (where high margins compress multiples) to mature tech (where high margins expand them). This structural change supports today's higher price-to-sales ratios, making the market fairly valued.

Big Tech's sustained outperformance presents a portfolio anomaly. These companies are simultaneously the largest market components and among the fastest-growing, a rare combination that breaks historical patterns where size implies maturity and slower growth, forcing managers to adapt.

The current market is not a simple large-cap story. Since 2015, the S&P 100 has massively outperformed the S&P 500. Within that, the Magnificent 7 have doubled the performance of the other 93 stocks, indicating extreme market concentration rather than a broad-based rally in large companies.

Many non-US companies are growing as fast as the Magnificent 7, offer significantly higher dividend yields (7-8x), and trade at a 30-50% valuation discount. This represents a rare cost-benefit opportunity that investors, who typically apply such analysis to every other purchase, ignore in the stock market.

Financial models struggle to project sustained high growth rates (>30% YoY). Analysts naturally revert to the mean, causing them to undervalue companies that defy this and maintain high growth for years, creating an opportunity for investors who spot this persistence.

Sacerdote argues the market concentration in MAG-7 stocks is not a sign of a frothy market but a logical outcome of the digital platform economy, where leaders grow bigger and capture most of the profits. He views them as still attractively priced given their AI-driven growth levers.

When a few high-flying stocks like the 'Mag-7' dominate the market, capital is pulled from other sectors, creating cyclical valuation discounts. Stable industries like healthcare can become as cheap relative to the S&P 500 as they were during the 2000 tech bubble, presenting a contrarian investment opportunity.