As always my journey improves and continues. These days I have pretty damn significant pleasure almost right off the bat and lasting most of the session. My body is still trying to "ejaculate" when I hit peak which seems to use a different set of muscles. I've been getting a lot of anal quaking and a slight tugging muscle spasm on my anal wall. Think of clamping your ass cheeks together, but instead of using your glutes they're kind of being pulled together from the inside. My question, is that the beginning of "clamping"?
@emancipation, no idea what you are talking about but relaxation is key. From what you are describing you may be tensing up without realizing it. When this happens try to relax even more.