catch of 40% per week!

theres this trader i know who at the end of the week keeps going on about his catches, he says on average his catch is about 40% per week. He trades cfds with margin 5%. so basically if he uses $10k for trading, then he buys $200k worth of stocks. so 40% of this is $80K. so he turns 10k to 80K every week!! im new to trading, is my understanding of catch correct? is anyone else experiencing similar success? Thanks

'at the end of the week'

could he at the start of the week show what he's possibly buying?

i think u have got this wrong, i believe he is saying to you tht he is turning his 10k into 18k every week, however most would not be able to achieve this with out risking a large % of their account per trade which means that sooner or later a bad run would blow your account.