I have a Peterson StroboClip HD clip-on tuner. I found the 'ACU' tuning, which utilises the 'James Taylor' offsets, to be 'sweetened' OK when capoed, but noticeably 'sour' when un-capoed (which is what you might expect, as JT capos a great deal, and his tuning offsets are designed to take account of that).

For my own use, whether capoed or not, I use the 'GTR' tuning, which is equal temperament - exactly the same as my TC Electronics Polytune Clip tuner.