Figuring out lines

Been playing .25/.50 6-max again and need to start testing some of my assumptions about the average player.

For example, have noticed an increase in the number of players who will cold call a raise behind and lead the flop, turn and river on low boards. My basic assumption is that the average player will not fire w/air into two players on the flop and turn but I think I've got this wrong. In looking at hands I've folded on the river, villain won 61% without showing his cards. Given that you only hit a pair on the flop 32% of the time and only improve 25% by the river, 61% of hands won without the cards being seen seems pretty high.

Over the next week, if I'm raised and get a cold-caller and a blind call, I'm going to go to the river regardless and see how it plays out. The math on a few scenarios indicates calling down with hands that are likely to be better than their range is +EV.

For example, you raise PF and get two callers, the board is low and one opponent leads the flop, both call. Turn is another rag and the bettor leads again, one fold, you call. You miss the river and bettor leads again, you call.

Opponent will hit a pair on the flop 32.38% of the time, he'll have air 67.62%. If neither of us have improved:

.6762(8.5BB) - .3238(2.5) = +4.94BB

If he checks the turn and then bets the river unimproved, a call is +3.58BB.

If the second opponent will call the turn because he improved, a river call is -0.78 but all you need is an 8% chance he is bluffing the river unimproved to break even.

It's still read dependent but think I need to try the call down approach for at least a week and track what happens. Will the average LAG fire blanks into a PFR on all streets on a raggy board?