Set the odds guys. Put all variables aside.....keep in mind all sharps, scrubs, poolssharks, the public no-nothings, etc etc. Basically, you are setting the odds of the average sports gambler long term. Profitable or not, keeping in mind some people are dumber than others while some are bright. Vegas lights are bright for a reason 
Will person X be profitable in sports gambling long term?
Yes. ____
No. _____
Break Even. _____
Will person X be profitable in sports gambling long term?
Yes. ____
No. _____
Break Even. _____