does that mean that tori should move out of the boundaries of the specific technique being taught, and start implementing his/her repertoire of henka waza, kaeshi waza or atemi waza on that person?
Oh my yes. If uke is resisting in such a fashion, you must change and adapt. If uke knows which technique is coming, even if you're stronger, they know exactly how to resist in order to defeat it. So, improvise, and do something else.
Training with resistance can be very useful. However, this type of resistance is spiteful, disrespectful, and a waste of time for tori and uke.