ONLY against a certain type of player. A tight player WILL NOT bet without a flush in that spot. Against them you need to bet out.
I have seen a lot more of the opposite "move" where you overbet when a big hand becomes possible. Amazing how many times (given, this is in chump change ranks) people call with anything when someone goes all in when the board pairs aces on the river. You can almost hear them through the computer saying "He CAN'T have AA or he would never bet that much! I call with my two pair!
"
All depends on the type of player you are in the hand with.