Two observations:

Appox. 60 to 75 percent of the money that's won or lost in cash games is bet on the turn and the river.

The terms TAG and LAG tell you lots about preflop and flop play, and a lot less about turn and river play, which depends on reads and prior action. Even the laggiest LAG, if he's smart, knows how to shut down on late streets when he's behind and can't push an opponent out of a pot.