The Claymore mine also uses pellets. The French built a larger version that had hundreds of tubes standing on end in a moderate sized box. You'd prop it up aimed more or less in the direction you wanted it to send it's payload, fire it from a remote site (another word for ditch or hole in the ground), and it'd cover a football sized area with lethal red hot pellets.
All AlQaida has in this is a modification of a well known process. They probably can't even get a patent on it.
They have definitely degraded the apparent intelligence value of Middle Eastern doctors and moderate Jordanian Moslems.