Would've interesting to see how long the actions took to perform for the first time vs for the 10th time (it's not apparent to me what they were actually measuring in the test).

Also, after having just read the title my immediate reaction was "duh". I've been aware of this ever since phones switched from keyboards to touchscreens. Back in the day I could text with the phone in my pocket, or while driving. Nowadays I have to steer with my leg so that I can operate the huge mobile phone with both hands.