The last bloom, with the two standards & two falls sounds like you had a chimera. These happen if the plant is stressed, such as from weather. Did your area have unusual weather this year? Such as a warm period followed by cold weather before the iris bloomed? If your friend is also having these blooms, and lives nearby, then it is likely that the plants have the same stressors. So weather is a likely culprit. Or if you both changed to the same new insecticide (the odds of which aren't high).
Have you had this on any other iris?
