In fact, it is very possibel to do what you describe. This requires though that you have skin that will shrink since it is not being excised. If the skin won't shrink well, then the ear incisions are required to remove it.
Why can't surgeons simply make an incision under the chin to access and tighten neck musculature in cases of Neck lift? I do not need a lower facelift; I just have a neck that does not match my face, due to cervical spondylosis. It surely cannot be too difficult to access and tie these loose muscles without drastic surgery. I look like a bullfrog at the moment, so Botox is unlikely to help me.
In fact, it is very possibel to do what you describe. This requires though that you have skin that will shrink since it is not being excised. If the skin won't shrink well, then the ear incisions are required to remove it.
The neck lift incision is an operation designed for removing excess fat above and below the platysmal muscle in the neck. It sounds from the description that there may be excess skin, and the neck lift will do nothing for excess skin. If there is extra skin in the neck, it must be dealt with through a full face/neck lift.