I lost a ton of money up until about 25 years old, Why? because I didnt have a clue. Many of the posters on here remind me of myself then, had all the chat, knew all the so-called tricks, hung out in the right places, never wrong and never ever admitted to being a loser. From then till about 10 years ago, I won a ton of money, Why? because I found out what it takes to win consistantly at betting. A complete understanding of prices and bookmaking, developing a sixth sense of spotting danger and above all, hours and hours of study. Since then I have had neither good nor bad years and realise that my profit or loss on average is dictated by the amount of time I put into it, thats why I am lucky if I win at any other sport than NFL, the only sport I really work at.
As for Arbitrage, scalping, middling, whatever you want to call it, of course one can make it pay. With the competition between books and the Exchanges growing, there is plenty of opportunities to make money this way. However, once again, its a time and quality of life question. When Betfair got going, it was quiet a novelty,and I got sucked into being on there all day and night. Although a good profit was being made, my health seemed to deteriate and socially I became a Hermit, not interested in anything else, frightened to go out in case I missed an earner. Many posters on here profess to win money regularly doing this, of course talk is cheap and the lack of discussion on bots tells a story in itself.
I have often heard punters telling bare-faced lies in Pubs and Race-tracks about their prowess and with the faceless internet it can only be expected that people live in a fantasy world, its only human nature, everyone wants to be seen a winner.