Re: 2% trading strategy, can this be applied for crypto trading?
the 2% rule means you don't risk more than 2% of your account on any one trade. if you have $100k, you don't risk more than $2k at a time. it's definitely applicable to crypto. it's a basic risk management strategy that hedges against variance.
even if your trading system is profitable, you could have a run of bad trades. if you trade 20% of your account at a time, you could blow up your account and lose your shirt after only a handful of trades. the 2% rule allows you to survive an unlucky run, and live to trade another day.
How can it work when earning only 2%? how about fees? or in 2% you already clear up all fees involve in trading and it's 2% gross earning/loss per trading
the opposite approach is the "all in on every trade" method that's so popular with crypto traders. 
I'm sometimes guilty on this with some altcoins. I just set limit, all in and boom. goodbye. next altcoins to trade please.