Let's make a list of all the methods handicappers use
Tail/Fade other cappers
Chase steam
Tail/Fade line movement
Tail/Fade public bets/popular bets
Rely on gut feeling
Rely on stats only
Rely on "inside information"
Rely on refs/umps only (see Donaghy)
Tail team's winning streaks
Fade team's losing streaks
Rely on the ability to sense the future (Seers)
Flip coins/use dart boards
Tail/Fade touts/"expert" opinions
Syndicates
Relying on systems
Let's make a comprehensive list.
The amazing thing is, you can win using any method and even have great streaks using any method imho. I think that's why you see people who are way too confident so often, they think their method is the road to riches when in fact they're not using a reliable method at all.
Another interesting thing is that you can have people who use diametrically opposed methods like those who rely on stats only and those who rely on refs/umps only and they both can have great success but they would give you completely different reasons for their plays and they would probably never agree if they spoke to each other about them. I find all this incredibly fascinating.