Actually, not too late. My first ALTER is still running, and I still have four more to go. Sigh. I had thought of this but wasn't sure how it might compare. Thanks for the data point :)
if all 5 alters' were to the same table, you should have combined them into one alter statement
Actually, there are six in four different tables.
But... I didn't know I could combine multiple ALTERs into a single statement. Thanks for the heads up.