[DownTownTonyBrown]

Here are the pertinent rules:

OBR
7.09
(k) In running the last half of the distance from home base to first base while the ball is being fielded to first base, he runs outside (to the right of) the three foot line, or inside (to the left of) the foul line and, in the umpire's judgment, interferes with the fielder taking the throw at first base, or attempting to field a batted ball; The lines marking the three foot lane are a part of that "lane" but the interpretation to be made is that a runner is required to have both feet within the three foot "lane" or on the lines marking the "lane."

NFHS
8-4-1g
The batter runner is out when:
he runs outside the three-foot running lane (last half of the distance from home plate to first base), while the ball is being fielded or thrown to first base.
EXCEPTION: This infraction is ignored if it is to avoid a fileder whi is attmpting to field the batted ball or if the act does not interfere with a fileder or a throw.
NOTE: The batter is considered outside the running lane lines if either foot is outside either line.

First of all notice that it is a "three-foot running lane." I've have heard some call it a 45-foot lane or those double "L" umps call it a 30 foot lane. It is referred to by its WIDTH - 3 foot.

(OBR 2.00, NFHS 2-21) Interference: offensive team act which interferes with, obstructs, impedes, hinders or confuses any fileder attempting to make a play.

I don't see it. A runner with his back to the approaching throw can't do much more than be a big target. Defense shouldn't have dropped that third strike or defense should have coordinated their throw/catch effort better - I've never seen it be very difficult.

Guess I'll have to do a Google search for Bfair's comments.