My theory is that the top 25 altcoins will outperform BTC in the long run, but on BTC downtrends, they will underperform and on BTC uptrends, they will overperform.
Just by judging by percentages? Yes, maybe, since the marketcaps are extremely different.
if someone has 2 million dollars in bitcoin, and it goes up, it's possible to sell for a profit.
but if I someone has 2 million dollars worth in another one, it's unlikely to be sold without completely crashing the market
for smaller investments, you might be right, although I must say I believe you stand a higher chance of losing a lot of money with such diversification.
When do you start testing your theory?