effective odds question

[Navers]

In TOP, Sklansky says to add up the total amount you expect to win and lose in future streets to determine whether to call or not (effective odds). Those are the numbers that you should use in comparison with pot odds. So let's just pretend that on the flop it's 4.5:1 to make your gutshot on the river and there's $65 in the pot and someone bet $10 (pot=$75). If you miss on the turn and they bet again you're getting $95: $20 ($20 because the betting doubles) Add in another $20 you expect to make for the river bet if the hand is good and you're getting $115:$20. You should call.

But if you miss on the turn, and the person comes betting again, you have completely new odds because instead of seeing two cards, you only have one left to see. You have $115:$20 odds but instead of 4.5:1 to make the draw, you're now more of an underdog to make it, so you should fold.

Doesn't this mean that effective odds doesn't take into account what you should do if you miss the turn? Should you just fold if you miss the turn, or was my math so off that in reality you would be getting good enough odds to call the river?