Trend vs. regression

[silentbob]

I struggle with this issue when betting any sport -- when there's a stat indicating that "team X is 8-2 in their last 10 games ATS," couldn't this stat be used to justify betting either way? I mean, it indicates X is more than likely to cover, but at the same time it's also likely that X's ability to cover isn't really 80% and will probably regress towards a more reasonable figure.

How do y'all decide what to do with a "trend" statistic? I'm a relative noob at sports betting and don't really know how to react sometimes.