[Thanos007]

The Crossfire event card "Cunning Plan" reads as follows: The Face chooses a runner. Flip up a card from the Normal Obstacle deck facing that runner. It runner takes an extra turn immediately after their next normal turn.

A turn consists of : Play Cards. Deal Damage. Take Damage. Draw & Buy Cards. End Turn.

So when this unlucky fellow completes his next turn he immediately takes another turn. 

Question. I am taking this to mean a full turn. Not simply playing cards and dealing damage but if the obstacles facing the runner have not been removed during the previous turn they get to attack again as well. Is this correct?

[Kiirnodel]

Correct.

Usually, when that card comes up, the Face wants to choose a runner that either A: can take a hit because their going up against another obstacle possibly twice. or B: plays later so that group can work on taking out some of the obstacles facing that runner (so they don't take double damage).

Or some mix of the two. For example, you might select a runner that doesn't have any obstacles right now and hope for an easy one that they can get rid of quickly. Or you might stack things up and hope for some help from the rest of the team (like with a Mono-whip or Covering Fire) to take the heat off.