You'll find the reference in the case book -- note that I used dots, not dashes (which would indicate the rules book).

Bob -

Ok Bob, I've reviewed the case book play you refered to, however I really don't think were talking about the same circumstances. Clearly the action taken by the BR in 7.3.5I would create a clear picture of interference.

In the play I referenced, as indicated in the varied responses, has a less-clear set of circumstances, where I believe umpires do have the latitude to view and decide 'yes' or 'no' to the interference call. Even when one considers 8-1-1c, "a fourth ball is called by the umpire," (a respondee added emphasis to the word "called")I still think were talking to the issue of prudent judgement. While I agree that the defense has the right to make a play, even if we're looking at a possible overslide at second base, I still believe that I would, in this case, try to 'sell' the argument that it was ball four, therefore before R-1 actually arrived at second base, that base had then become an award.

As I stated earlier, and CC suggested the same, R-1 who ended up on third base because of the errant throw would then be returned to second base, relying on 10-2-3g, and simply explain to the offensive coach that it was 'return' or batter is out on interference and R-1 returns second.

I suppose if one were to declare interference, then one could also argu the case that R-1 should return to the base occupied at the time of the pitch. "What!" R-1 gets sent back to first base? It could happen, couldn't it?