I disagree, if you move half the distance to the door, you move 4ft. Now, you get to move again, but you only can move half the distance to the door, which is not 2 ft. It is worded correctly because you have to assess the next step after the one before. "Remaining" is not a necessary word in the puzzle.
Toirtis, I understand what you are saying, and it is vague, but I believe the wording is still correct.
Did we ever hear what the "correct" answer to the 2 doors riddle was? I think there are many answers but i'm curious as to what the intended answer was.