When I address the ball with the M4 driver, it feels like the club face lies naturally open (right of target). In other words, I feel like I need to slightly shut the face in order to make it square (neutral) to the target. Does anyone else have this feeling?
You can actually adjust that with the loft sleeve. If you adjust the loft to the highest setting, it will close the face. If you want it to look even more shut, you can jump to the highest setting and increase loft as well.
Thanks Allan, but, I am confused for two reasons. If I adjust the loft to a higher setting, I would increase the loft, right? Suppose I want to keep the loft as is but square the face (make it not open to the target).? Second, if I adjust the loft to a higher setting (say 10.5 to 11.0) will this actually make it more open?
As you surmised, The loft sleeve affects loft by altering face angle. When you move the sleeve toward the higher setting, you're closing the face at address. The increase in loft happens if your face angle at impact is the same as it would have been with the loft sleeve in standard. In other words, if you're able to get the face open at impact relative to the face angle at address, you will have added loft.
The opposite is true for lower settings. Moving the sleeve toward the lower setting opens the face at address. The decrease in loft happens if your face angle at impact is more closed than it was at address, which has the effect of shutting down the face and lowering the loft.
If you're able to retain the same face angle through impact as you had at address, then the sleeve will mainly affect only face angle and won't cause the loft to change much. Because loft and face angle (and lie angle) are all intertwined within a single setting on the sleeve, this is the only way to change the face angle without affecting loft. So your question is answered best by saying, "It depends upon your impact conditions."