I've always seen these threads as one of the most popular ways of stedily increasing your bank and if you pick your games carefully then it's a very good way of making money.
But the threads always die out around the 50-60 bet mark.
I imagine the best way to do this is to bank off £100 every time you make £130 or so to not bust yourself by getting unlucky but i've yet to see a thread of someone who has stuck at it and gone from say £10 to £1000