I would rather call the FPSR, evidence that play was altered is the bad throw, and eject the offensive manager if he wants to be ejected, instead of rewarding him for teaching his players to play illegally.

I can also see a bad throw being a possibility without INT but altered throws due to runners sliding illegally generally are awkard looking from the start. Picture this, F4 jumps in the air to avoid runner sliding illegally at him and makes a bad throw. I am NOT rewarding the offense for this illegal activity.

Wrong, but you seem to correct yourself...

Then you have an altered play, and you can justify the INT call.

We are judge of whether play was altered, but slide toward the fielder is clearly illegal, so judge on the side of penalizing illegal if there is any question about it.

As a friend once told me about a balk he called, coach complained because he said he teaches him that move - well coach, don't blame me when I catch him doing something illegal you taught him.

I agree that's what the rule says, but I read it as "if he slides it must be legal; if he doesn't slide, he must run in a direction away from the play."

Again, this has been discussed many times, and no clarification from the FED (other than the one interp several years ago where R1 was "lesss than halfway" to second when he was hit by a throw.)

Be careful here: the rule sets a much higher standard that what you suggest. The relevant rule for interference when a runner does not slide is 8-4-2(b):

Here are 3 distinct standards:

1. Runner must make no attempt to alter the play.
2. Runner must attempt to avoid altering the play.
3. Runner must avoid altering the play.

The first two concern what the runner is trying to do. The rule says nothing about what the runner is trying to do. If he makes illegal contact or illegally alters the play, then he is guilty of interference, whether he was attempting to alter the play or attempting to avoid the fielder.

In other words, the third standard applies: he must successfully avoid altering the play.

Bob referred to the definition of an illegal slide. Here it is:

Bob pointed out that clause (c) refers to making contact; clause (f) does not, nor does it even refer to altering the play.

Bob, I didn't write the rule and I really don't care if the runner disappears in thin air, slides, runs the other way or maliciously contacts the fielder. If he slides, it better be legal, if not, he better not alter the play.

But, if you and others have a problem with the way the rule is written, then your problem is with NFHS, again I didn't write it.