Poker players use something call a bankroll for managing risk. The amount of money needed to play at a level (called a limit) is called your 'buy-in'. So you might be at NL50 and the buy-in is $50 and the next limit is usually double, so NL100 or $100.
Mathematically the buyin is calculated using the risk-of-ruin formula for blackjack but an accurate rule of thumb is that to play a limit you need 20 buyins MINIMUM.
so if I have $1000+ or $50*20 then I can play NL50. However if I wish to play NL100, then I must win an additional $1000 to move up to NL100 ($2000 bankroll).
It's a way of hedging your risk so that you don't go bankrupt.
Now the question is asking me if I want to bet my ENTIRE bankroll on Bitcoins. That means I'm using a 1-buyin rule. Not smart at all. If you lose then you're bankrupt.
However if you though BTC is going up then you can bet a portion of your bankroll depending on how risky you think it is (somewhat risky = 1/20th of my bankroll, very risk = 1/50th).
Anyone interested more can read here:http://www.liquidpoker.net/pokerarticle/146441/The_bankroll_management_and_variance_guide
That's all correct. But the exact same applies to the USD. Since the question forced us to abandon BRM anyway this doesn't tell us which way to go.
You are actually more fucked if you have everything in the dollar when it goes because all the people around you who could help you if you were the only one who lost it all are also ruined now.
To be clear, I'm not putting everything in BTC, but I'm not putting it all in the dollar either.