SEC Form 13F makes portions of institutional equity portfolios publicly observable, but only with delay and only as quarter-end snapshots. This paper studies a behavioral and practical tension: many investors verbally acknowledge that a “super-investor” (e.g., Buffett or Li Lu) is likely superior to their own stock-picking, yet still retain a discretionary trading sleeve. Under a long-run log-growth (Kelly) objective, that choice is not merely a style preference—it becomes a consistency question. The framework separates two questions. First, when is delayed cloning viable after accounting for information staleness and implementation frictions? Second, when mixing is feasible, when is an all-in clone uniquely optimal? Using a tractable diffusion benchmark and a reduced-form lag penalty, the paper derives (i) a simple viability condition, (ii) sufficient conditions—including an explicit correlation threshold—under which any positive weight on an inferior, positively correlated discretionary sleeve strictly reduces expected log growth, and (iii) a closed-form “Cost of Ego” that prices the compounding sacrificed to preserve subjective control. An empirical calibration (Berkshire Hathaway and Himalaya Capital) is used only to bound the lag-cost channel rather than to claim that 13F cloning “beats the market.” The estimated annualized log-growth penalty from a one-quarter delay is on the order of 0.4%–1.2% in these low-turnover cases, providing a concrete scale for the common “delay fear” objection. The paper concludes with operational deliverables—how to compute the effective lag, turnover and continuity proxies, and how to apply the viability and consistency tests in practice—along with transparent limitations (13F’s structural blind spots, discrete rebalancing and jump risk, and the distinction between rational cash sizing and an ego-driven inferior active sleeve). This is Version 1.0 (2026-02-14). Please cite the Zenodo record’s version DOI for this release.
Meng Fang (Sat,) studied this question.