What do you say when other ask you about your homeschool day?

What do you say when someone ask you about "seat hours" or how long your homeschool day is? 

A friend of mine is a public school teacher. She was almost appalled recently that we ONLY spend 2 hours a day during book work. I tried to explain that we don't have to count the hours we spend, just the days, but that didn't seem to help. I tried to explain that things go SO much more quickly when we don't have to wait around on others to finish up, line up, or shut up in order to get done. I also tried to explain that we review throughout the day and connect things to other things all the time. We get to expand learning to more than just the hours spend "at school." 

Afterwards, I thought about this. I was very troubled because I don't want anyone to think my daughter is getting an inferior education simply because she is being educated at home. I talked to other homeschool mamas and they said for me to not let it get to me. They said that I don't owe anyone an explanation. While I agree with their advice, I also disagree. I don't want someone to look down on my child (now or at some point in the future) simply because she is educated at home. I was hurt because I am a former public school teacher. I know the standards for the different grade levels. I know what needs to be covered over the course of each school year.  BUT I also know the amount of time that is wasted each day at school. So was my friend doubting my knowledge of standards and curriculum? Or does she actually think that I am allowing my daughter to just play and have fun instead of teaching her the skills she needs to know? 

I thought about whipping out my lesson plans and showing them to her. I thought about allowing her to quiz my daughter on recent topics we've studied. I wanted so badly to prove to her that my daughter is getting a quality education...and I still do. HOWEVER, I realized that in public school there is never enough time. My friend can't fathom how I could possibly do in 2 hours with what take her all day. You see, my friend has 20+ students on at least 19 different ability levels. She has students with behavior issues, students with IEPs for their special needs, and students with undiagnosed issues. She has administrators and parents making demands. She has fire, tornado, and intruder drills. She has bathroom, recess, and lunch breaks. She has interruptions from miscellaneous announcements. She has new students brought in with no prior warning. She has students who don't have the proper supplies. She is constantly trying to meet all the needs of all the students in spite of all the interruptions. 7 hours is not enough for her to cover four core subjects with all 20+ students. But 2 hours is more than enough for me to cover those four subjects as well as handwriting, typing, 2 foreign languages, and Bible. I would love to show her.