Tales from the LBS.... When the day starts like this you KNOW your in trouble..

[BleeckerSt_Girl]

I have always found it best when dealing with either children or cave men (or cave women), to just tell them initial answers in terms of the simplest statement possible. Such as "Those won't fit on there."....."We are not having ice cream now."....."I need to know the size first."...."This one is better for you."....etc.
I'm not saying you did this in this instance, but Caveman's impatience reminds me of when I see mothers do this with their kids- The kid asks if they can go to Johnny's house after school. The mother says "I don't know if that's a good idea since your sister has a dentist appointment at 5 and Daddy is driving the car with the extra seat today and I need to pick up my friend on the way, so not everyone will fit in my red car. Maybe we can ask Johnny's mother if you can go there tomorrow instead." Meanwhile, by the time she said "I don't know if that's a good idea....", the kid had already sized up the answer as "No." and ran off to another room .

If you start by giving them a clear detailed explanation, many children and cavemen types' eyes quickly glaze over and they look for someone who can give them a simpler answer.
People who are capable of grasping the finer points or terminology will ask you to elaborate on the details of why or how, after your initial simple answer.
Perhaps a little of this came into play with CaveMan?
You might have lost him already at bottom bracket, truing the wheels, and extended valve stems. Just an additional thought, might not apply here.