I just read your post: It is a plausible sceanario.
It could happen!... I think it is enough if we scatter and disorganize the Al Quaida group.
This problem will not go away in any short time. Remember how long the battle has gone-on really. For a time reference, look at the crosses atop Russian Orthodox Churches across the Volga region: There is a cross, set into an upturned half moon. This is symbolic of the victory of the Slavs over the Islamists and their freedom from Islamic slavery.
Seen this way, all of the rumors of "OBL is dying of kidney disease", "OBL is dead" etc could be rumors started by himself to increase the myth value if/when he makes his "miraculous appearance" on the balcony in front of the ecstatic millions.