It's all about Exposure Level
Which, for 95% of the people who read this post, means that to mae any kind of significant profit on a series of -200 (over whatever period of time), one must expose far too much of your bankroll.
Let's say you want to win at least $50 on an average wager, which happens to be - in my humble opinion - larger than the average size wager for the vast majority of people who use our forums.
Let's further extend the discussion to presume you have an available (without risk of harming yourself) balance of $1000. Again, a larger amount than most people who use our forum, but let's use it.
To win $50 on a -200 fave, you'll need to Expose at least 10% of your bank.
If you do that five times and you win once or less, you've just hammered away 40-50% of your bank.
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NOW IF you happen to be someone who honestly has a larger bank....Say $5000 and you make same wagers and go 1-4, you've only lost about 6% of your bank.
I stopped using larger priced Moneyline favorites about 18 months ago in NHL and MLB because my available real world bank is nowhere near $5000