harvydonald
I truly accept your argument and as I had mentioned elsewhere, there are always exceptions. This may be one of the reasons, why USCIS is nowadays asking that the local-office be also informed of address change if there were at least one petition that was either adjudicated or pending adjudication by the local office. Also, usually when a petition is adjudicated favorably, it doesn't really matter, however, if INS should observe something in a petition that may result in a denial to the petitioner, then, it will not be in INS's best interest to have jurisdiction and venue issues defang its decision. (The Appellate Courts will summarily dismiss its decision to deny based on the jurisdiction and venue issues, if the petitioner disputes them in his appeal.) Hence, more than the petitioner, it is for INS to be sure that the right office interviews the right petitioner/beneficiary. That much said, there are instances, such as the one you have posited, where INS may have done precisely the opposite.
Even then, I will justify in your example as to what INS did was perfectly logical. Kindly allow me to explain. Your friend filed AR-11, but did he intimate the Florida local office about his moving to Houston? Also, when the Florida company had bought the Houston Company, they did the right thing in transferring his petition to Florida and when he was subsequently laid-off by the Florida Company, did he officially intimate about this to the Florida local office, citing AC-21? Nope! Now, with these issues at hand, how can the Florida local office know that the guy is not working in Florida anymore or even is laid off? Due to a paucity of information at its hand, it merely assumed status quo to continue and hence summoned him for interview at Florida.