Neither torque nor horsepower explicitly takes time into account in the discussion. The torque or horsepower is calculated instantaneously for rpm X, then for rpm x+1, etc, until we generate the discussed curvilinears. Yet, in practice, such as in the acceleration of an automobile from idle rpm to it's maximum rpm, we now have taken time into account and can calculate the torque across that entire time period; this is no different than Power(horsepower) as regards the temporal element.
Yes, it is true to say that one can calculate velocity by measuring the distance travelled over a defined time. But, it is not a necessary condition that time be considered. Any variable can be described as to it's value as a function of time, or it can be described in an instantaneous fashion.
If one is to say that velocity is unequivocallyknown by measuring the distance a body travels over a known non-zero period of time, that is false, in principle. A Body A, at t=0 resides at Point A. One hour later that same body is at Point B, which is 100 miles from Point A. Does one then say the velocity of Body A is 100mph? I can envision Body A travelling that 100 miles over a time period of one hour, but sometimes having an instantaneous velocity of 200mph, sometimes 0mph. So, 100mph is only assured to be an average velocity. In principle, the true velocity of that body, if it be 100mph over the distance of 100 miles, can only be stated if all (which is impossible, in practice & principle) instantaneous velocitie's are known (instantaneous velocities have no time nor distance components, just a relationship with some arbitrary reference frame, even if it be a reference frame fixed nicely for our little measurement exercises). So, what is an instantaneous velocity? It is a velocity that has no finite time component. It has a time component, but since the time component is always zero, no time vector exists for each and all velocity measurements. Power is no different. Any fondness to name this or that variable as "dynamic" and another not to be so is not good thinking and is rife with arbitrariness and assumptiveness. It is the instantaneous values we have, and that is all we have. We can graph the instantaneous values as a function of time surely, but you are not correct to say that you have taken time into account when measuring power or velocity or torque or acceleration, or anything else for that matter. As soon as we take non-zero time into account we only have the average value of whatever we are measuring as expressed over an arbitrary interval of time and have buried the instantaneous values, which alone have any physical meaning. As soon as we throw time in the mix we lose the true velocity (or power or torque, etc) and are left with an average.