"I guess that is my reasoning for formulating my own strategy so that if my profits start to sag then I can tweak my approach rather than buying a different package."

Fair enough.

I've done quite a bit of handicapping myself, but I'm more interested in making money. I like sportsbetting, and it's a great job for me. I like analyzing it all etc but it requires more hours than I want to put in, since just betting all the picks I get is a reasonable job (should be around 9k straight bets next year, then throw in the arbs, middles, teasers etc).

"is that betting markets change year to year due to, for example, an increased participation of online punters and the increase of info available to punters. A strategy might work well for a few years and then falter as the area you punt on gets targeted by pros or the info you once had to dig for becomes readily available."

Depends on the maturity of the market. I have no doubt that tennis will become tougher, but it should always be beatable for a decent amount. Bookies just won't be able to spend as much time as a dedicated handicapper. The main reason I think atp will become tougher is because it's not a heavy public market compared to the different football leagues, so you'll get more informed punters, and since you can get quite alot of money down, it forces the books to become more efficient (because a greater % of the action is sharp money).

Heavy punters markets like the american sports (esp football & bball), soccer, and the diff footy codes will change much more slowly as the sharps represent a much smaller % of the action.

Basically I'm saying the tennis market will become more efficient, but it'll always be beatable for a decent amount. This market has already sharpened up quite a bit anyway. A technique that works now for a decent amount will work in the future, unless something in the sport totally changes (eg nhl).

"the area you punt on gets targeted by pros or the info you once had to dig for becomes readily available."

Tennis has already been targeted by pros. The market responded by becoming more efficient. Most successful cappers haven't done nearly as well in '04 and '05 as they did previously (although my sample size is only around half a dozen).

Info becoming readily available doesn't matter unless people are able to take advantage of it, and a huge majority of punters don't have the skills to do so. Look at more efficient markets like the footy codes in Aus, or football or nba in the US. They have MUCH more info available than tennis, yet nearly all the punters are as dumb as ever lol.

If a capper can beat a sport for a good amount, it's likely he has the skills to adapt to changes in the market.

"if my profits start to sag then I can tweak my approach"

Easier said than done, since variance is so large. It's quite possible to go 15% for the first half of the season and then 2% for the second half. It may be variance, it may be that your system isn't all that good anymore, or it may just be that your system doesn't suit something that occurs in the 2nd half of the season (eg surface).

Think that's enough, it's hot and I need a swim.