Hi,
I had 2 Dobs during my initial beast experimentation. Cookie & Simba. Well, I still have them, but now they live at our farmhouse and not with me. (Long story).
It was always a tussle to hold on to Simba as he was much more frisky and was agitated whenever stuck. I could never 'control' him well and he would inadvertently pull out without going soft. Cookie was more accepting of soothing words and generally dismounted me on one side, usually with one leg lying over me. I love being ass to ass with dogs (makes me feel more animalistic) so I would casually twist away and try to 'shrug' him off so that he would take his other leg down too. I did this because generally when I tried to move him with my hands, he would perhaps feel that I want him off and he would then try and dislodge his knot causing me discomfort. All my orgasmic high would disappear with the pain they caused.
Dobs are good dogs to nail you but their guarding instincts work against you at these times. perhaps the feeling of being stuck makes them feel vulnerable and they want to get back to their 'zone' quickly. I don't know. Not an expert
They have a more than average size of knot so it stays in for a while (even in a used up pussy like mine)
Both don't have tails so I can't hold onto it (like I see Vixen do it in her videos). I mean I tried to learn how to 'hold on' through videos but I am not tall and both of them are almost my height (while on all 4s). I was never able to get a good grip on any of their hind legs and so I have only tried to stay tied safely with soothing words. One other thing I tried was to knot at the edge of the bed so that they would be wary of jumping off the bed. Unfortunately a couple of times it didn't work out well and they did jump off leaving me yelping in some serious pain.
The stray dogs I do meet (after they were taken away) are much smaller and have relatively smaller knots so i can hold on to the dog or even if they come out, there is not much distress for me.
So, I am yet to nail the perfect method to stay knotted in place for long. Have tried Kegel exercises too. Doesn't work for me. I guess a partner holding him in place would be ideal but...
DS