If Apple beat Berkshire Hathaway’s evolution more than 100 times since their inception, how do you manage your portfolio’s diversification?

Hello,

I used Marketcapof ROI calculator recently to calculate the evolution of two companies : Berkshire Hathaway and Apple. Since the moment both went public, Apple increased 134,000% times while Berkshire did a merely 1400%.

I've heard the phrase that 'diversification is good for your portfolio' more than 100 times, but with this difference in earnings over a large span of time – what do you feel it's better? Bet large ( 20-30% of your portfolio on a company) or pick multiple high potential stocks with 1-2% maximum.

Thanks