AdjustedEarnings, SwedishValue, khturbo, Jurgis & Lemsip - Great points.
Most reasonable people estimate future growth in total earnings power at Berkshire to grow at between 8% to 11% (my own range is 8-10% with 9% as my central expectation). To avoid confusion, I say total earnings power instead of IV, because IV is dependent on the growth rate.
When you take a growth rate of 10% or below, the only way it would be worth 1.5x BV or more is if we use a discount rate that is lower than that. Banal observation. But without specifying one's discount rate the justified BV multiple does not convey the full picture. I like how khturbo made it explicit.
Vinod