Yes, me too. It is important to have a very thin and large "coffee table" type book, or a clipboard. Shove it up against the tendons in your crotch good and firm (move "things in the way" to one side), but not so much that you are obviously manipulating the measurement longer than implied or trying to lift the subject off the ground. Keep the book at 90 degrees to the wall. Take the average of three measurements. I have read to do this in your thin cycling socks, and a framebuilder I worked for did it this way.
FYI: my cycling inseam is 867 mm, (33 and 15/16ths of an inch). I had a long torso/short legs as a youngster, but over time I lost torso length faster than leg length. I am 5'10", about three quarters of an inch shorter than 43 years ago when I got a custom racing frame.