Think it's taken Donglemouse about 18 months - 2 years. Worth noting that some of the bookies he used in the early time are dead now and some of the others who are skins of each other have wised up but there's still plenty of cash out there if you go looking.
They've all kinds of ideas for making money through various gambling bits 'n' bobs over there. Thing is though not many of them are actual gamblers and thus don't know what they're doing (some do and the mod of the forum Tim_L i think is pretty good at spotting people who really haven't a clue and stopping them posting complete arse).
Having said that I saw one thread (after it had all gone tits up) which ended up with several people losing thousands (biggest was £12k) because they thought they had a good dutching system on a market (first goal scorer i think), they didn't understand that half the money wouldn't exist if the player didn't start and used the implied winnings to back others so actually lost more than they had in
betfair to start with (which i must confess hadn't occured to me that you could do).
The matched betting is sound just remember the old saying about anything else you spot if you look over there "if it looks too good...blah blah etc.."