To continue to beat the dog - the SHAFRIR was built primarily to up the
missile inventory numbers but to also provide a Sidewinder type IR weapon
with a larger warhead - and that was the reason the Sparrow was so popular
after the Phantoms showed up, but the Mirages, Neshers and Kfir's needed the
same "edge". The edge is not having an enemy shoot at you after you
effective "kill" him with a valid missile shot and hit then go screaming by
him and he pops off a missile just before he crashes, explodes, or ejects.
the big warhead was to create catastrophic destruction on impact to ensure
better survival of the IAF fighters.

The SHAFRIR's envelope was no better then the AIM-9B (30 degrees off the
tail if you were lucky) but that was obtainable by the IAF pilots, it was
the catastrophic destruction that was important and that has carried through
in all the Python models.

The eveolution is seekers brought high-off boresight shots to the head-on
arena to the full "first-sight - first kill" realities of today's multi-band
heads.