Here are 3 Moire patterns. On the left is the pattern displayed on the laptop. The middle is taken with the 7D from 3m away after focusing it as well as I could using MF and LiveView x10. The right hand pattern is taken with the 7D from the same position using LV, AF and IS all on. Both photos taken with the camera had a 2-sec delay. The RAW images were then opened with Adobe canon Raw 7.4 then PS Elements. Both got the Auto levels with Exposure reduced to avoid over-exposing the image of the pattern and the following Sharpening and Noise Reduction:
Lum Detail 50
Lum Contrast 0
Color Detail 50
I'm not 100% sure the images are as sharp as they should be. However, I can't see any degradation caused by AF, nor did the focus move when I changed from MF to AF.