IMHO, there are some interesting implications.
If I use the blade of my hand to cut, I move it differently than if I push with it.
In sword work I control the tip. If I use my arm/hand like a sword and control where the tip would be, I seem to get an better extension of the technique.
I also notice the following observations:
1) A person (uke) is strong or able to resist if his tegatana is directed towards his partner (nage)
2) that when you return uke's own tegatana to himself makes good technique. There are a lot of interesting applications: ikkyo, nikkyo, sankyo, yonkyo, kotegaeshi, shiho nage even kokyuho and kneeling pins as prime examples. You can see it in a multitude of other techniques but its quite subtle. 2 tegatanas (both nages and ukes) toward uke increase a technique's effectiveness. A technique is not effective if either nage's or uke's tegatana is pointing/facing somewhere else other than toward uke.
It makes sense though because the tegatana is one of the most powerful parts so neutralize it in order to weaken partner.
To then start weakening/controlling a person is to return his tegatana to him or redirect it so that it is not facing nage. I'm currently testing this theory of mine and so far has yielded some very interesting results. It's a rather very simple idea but it changed everything in how I approached training.