[perl4ever]

Diversification can mean different things to different people.

If you mean that >30 stocks is pointless, I agree. How much different is the Dow than the S&P 500 or the whole market, even though its methodology is atrocious?

If you mean that even with a large edge, you should take positions that are >20%, I don't agree.

[manigandham]

Then we don't agree. The concentration of a position depends on the confidence of the investment and direction. 20% isn't a magical rule, no point in following it blindly.

[perl4ever]

I mean, it's like sticking a knife in an electrical socket. Can you get away with it, possibly? Sure. That doesn't mean there's a significant downside to a rule of not doing it.