Time awareness

I have a question about people with ADD/ADHD and time.  It's often said that people with ADHD aren't aware of time and so don't realize how long it takes to get things done.  Do you think that it's also possible that they don't realize how "short" it takes to get certain things done?  This thought occurred to me just now while I was in the kitchen waiting for some cookies to finish baking.  I staightened up a bit while waiting and thought about one of my routine "while waiting" tasks:  emptying the dishwasher.  I can do most of it in the time it takes my coffee to heat in the microwave.  I wondered if my husband wouldn't think to do something like that because he has no idea how quickly the task is accomplished.  Any thoughts?