More results with less effort
I think we have agreed upon the treatease of having the ability to use strength that will entertain a more viable practice ... in that we are not made of glass and we will not break, but that is the long way around to finding that little key to most techniques is the ability to "Get more results with less effort."
As in most physical labors of your daily life, there are ways to do labors effeciently, and then there are ways to physically power through these labors. I entreat you to take the lessons of Judo, and build upon them. If I were to hold on to you when thrown in a typical upper body throw, the thrower would need to have proper rooting, strong stance, to resist from being thrown by his/her own technique. Proven fact of my experence from practice. If you need more lessons in learning this, then seek out the basis of rooting, and apply it when throwing, I bet you will be more able to change and adapt more adeptly.
You see Bob, I have been the strong upper body gorilla with arms like most peoples legs, and although it was easy to leave the center of everything in the upper body, it created too many openings for those who learned the lessons of "More results with less effort" to easily overcome my strength.
I don't say be so gentle as you are hindering practice, but to shift this effort from using strength to cause movement, but using movement to accentuate movement is the efficient way to move.
This is the simplicity pushing a child on a swing, or pushing a merry go round as it circles, simple movements of childhood applied to the martial arts. Many of my bad habits were broken by using a rowing machine for extended exercising. It was a shadow of really rowing a boat for five or six miles, but it did remind me of how to use the body in an efficient unison movement rather than isolating arms and upper body.
Shifting the focus of your efforts from your arms to your fingers/ hands should begin to enlighten you to what I alluding to. If you begins to lose the feeling of arms and forearms doing the work while mentally picturing your hands reaching across the room, the strength of no strength will soom be yours to explore.
The mental connection of the mind having the proper signals to accentuate and improve the movements of the body are the same as lifting weights to improve the muscle tone. It takes repetition, and it takes practice.
Consider. Stand your jo, or a broomstick on end ... as it falls increase its motion by slapping the top of the stick at the top. Stand it up again, and slap it at a lower point. Stand it up again ... slap it at a still lower point.
Now, did it take strength to increase the motion, at the top, or did it affect the motion quicker as you pushed lower?
That is your physics, but now we are going to change physics.
This time tuck your elbow to your ribs and do the same experiment ... you might have to turn your body to accomondate the movement needed to move the stick.
Did you need less effort to move the stick or more effort? Was it the physics of using more body force than the speed an muscle of the upper body, or was it that you were using the forces available in a more efficient manner?
Physics explains what is possible ... but only when you are aware of the possibilites.
There is more than one reason to tuck your elbows in to protect your ribs when sparring, and Aikido shows us that accentuating movement from efficient use of body movement, our use of the body's center, is achievable with excellant results.
Maybe I have overstated my point, but being able to muscle through most people was at the beginning of my training, and now , after a long illness, I have found another way to be just as strong without all the exhausting physical effort.
Consider this practice but another way to give you wind and energy to extend practice. It is kind of like finding the math as an explanation of the movement, it is not the reasons for having the movement.
Also see, I have given you a means to understand the small sensei throwing the big muscular student.