blocking bets - what am I missing?

[meow_meow]

I don't use blocking bets, but maybe I'm missing an important concept.

The way I understand it, a blocking bet is a smallish bet (say 1/4 pot) on the river when you are OOP, in an attempt to prevent villain from making a large bluff.
Is this more of less correct?

Considering only ss NL here, say 200NL and below.
Isn't it preferrable to check most times and induce a bluff (which will usually be <1/2 pot)? If villain has missed his draw, he won't be calling the bet, and you'll be getting more value by check/calling. Of course, you'll sometimes be called be weakish holdings that would have otherwise checked behind, but doesn't that make it a value bet in the first place?

On the other side of the coin, if villain has you beat, he is likely to raise, at which point you'll either be folding (in which case check/folding was a better option) or calling (in which case check/calling would probably have been cheaper).

What am I missing here?