in 1998, I visited a board called hotcopper. I guess things don't change much. This site looks slightly more sensible.
I am amazed that people still expect 10-20% pa real returns on a consistent basis and 50% or such on a leveraged basis. This is a warren buffet type achievement : extremely unlikely year on year. At 20%pa a mere $1000 grows to 9.1 million in 50 years. At 50% $1000 becomes 638 billion (in todays dollars this is 10% of the M4 in the US) in 50 years. No one that I am aware of has been able to do this. It is obvious that high returns over decades are extraordinarily difficult to achieve. There is only a finite amount of real wealth on our planet, and if everyone grew their investments at these speeds soon all the wealth in the world would be insufficient to sustain the returns. Economies, markets and I suspect trading accounts experience k-waves that self correct the system.
I suppose the hope is that you can build up your trading capital through these big gains initially and then preserve it. Unfortunately by doing this you drastically increase your chances of blowing out. And even if you are lucky enough to accumulate enough trading capital you will almost certainly blow out at some stage. Faster is often slower, and perhaps a portfolio aiming at a real return of 5% (or 1 % above the historical mean) is more realistic, likely to be more structually stable over short and long time periods and have a much higher probability of success.
A decade I read a book called the richest man in babylon, it is still one of the best books I have read. Compounding is something that few people understand.