Blame it on the volcano?

My flight from Frankfurt to Boston was delayed by just over an hour. When the announcement was made in the lounge, the flight was apparently delayed "due to the volcano" - although the German version of the announcement made no such references. And seeing that the flight did take place, just over 90 minutes later; with the flight path directly over Iceland, it raises the question - are all delays for the next while going to be blamed on the volcano?