I have a more varied routine now, but when I started, I fowfered all day long. I could go as long as 45 minutes at a time, after which I’d have lymph fluid in the shape of the creases on the glans that formed by sitting on it. I’d give it a few good swings, shakes and squeezes to restore circulation and when it looked ready (5 minutes or so), I’d tuck it in again. When I have a choice, straight up the crack on either side of the sack gives me the best stretch. I also would squeeze some blood into the head to make sure that it pulls the entire length of the shaft, otherwise I would get an intense pull at the base, but the rest of the length was less stressed. I have to lean back a little to get my tailbone to sit right on top, but it is provides a more effective stretch this way. Under the leg is okay in the car, but it doesn’t stretch as well and blood flow is much worse.
As for your weird sensation, I can’t be much help without a more specific description. The skin stretch was pretty intense at the beginning. I wasn’t so careful and got crazy stretchmarks, but that can be avoided if you go slowly. Skin stretch can cause itching, as well. I would say it is impossible to get too much tension on the ligs with a fowfer, but it is a strange sensation at first. It may be loss of sensation/tingling due to reduced blood flow, which is somewhat unavoidable, but less so going straight up the crack. It may be worse if you have a skinny but, which I certainly don’t have. Most of the vets here would probably say go with shorter sets if it starts to loose color or get cold.
My biggest discomfort was in my scrotum, as it is high and tight. Fowfering to the side has helped this a great deal, as well, but it was very uncomfortable in the beginning. Like getting kicked in the nads, the pain has a tendency to radiate or disassociate with the source; at least it did for me. I just had to keep repeating a familiar [url=http://www.imdb.com/Find?select=Quotes&for=fight%20through%20that%20shit">quote until my sack relaxed and started to stay that way. :)