Thank you, but I think your assessment is too generous.
A horse can be an overlay at 3-1. In fact, overlays can, and very often do, occur at lower odds. If a horse is 2-1 (as I believe Empire Maker was in his Belmont), but should be even money, then he is a substantial overlay. A horse at longer odds will pay more, but may not represent better value because proportionately he may not be a larger overlay (i.e., his actual price may not, in relative terms, be as far removed from his true odds as those of a shorter priced horse). Moreover, his probability of winning, even if based on his true odds valuation, is, by definition, less than the shorter priced overlay. Hence, a longer priced horse, even if a legitimate overlay, does not necessarily have more value than the short priced overlay.