A very good post and so very true - the SNB tsunami was a lesson in why using leverage beyond 3:1 is suicide.
For many, the fixed stop losses were useless as liquidity dried up and price just shot through stops like a hot knife through butter.
I'm a signal provider on two on the more popular sites and still there are precious few who can offer a verified track record of over 12 months trading.
Why? - Most over leverage trying to build small accounts into large ones too quickly.
Arguably the greatest investor in the world, Warren Buffet had a long standing track record of achieving around 20% return year after year. Yet the hype around FX suggests people can achieve 10%+ per month - sure its possible but its likely your account won't be around for too long to ever truly benefit from compound growth.
LOW leverage is in fact dangerous. WTF I am saying that?
It is simple - to get the same profit you need to invest and thus risk more money.
Lets say you wont to trade 1 lot of eurusd with SL/TP=100 pips.
With leverage of 1:3 you need 100000*1.12/3= $37,000 to cover the margin so you have to have account of $40,000 to trade 1 lot.
You are risking these $40,000 as anything could happen.
With leverage of 1:500 you need 100000*1.12/500= $224 to cover the margin so you have to have account of $1000 to trade 1 lot.
You get the same profit or loss on both accounts. Lets say $100.
For 40k account it is just 0.25%
For 1k account it is 10%.
So it is much better to have 40 accounts of 1k with high leverage and diversified portfolio of broker/pairs/strategies than have one 40k account.