Weird sytle of Aikido?
Clarity. Knuckles are used to activate rub or strike pressure points, which we do not instruct in Aikido, as the third pressure point on a meridian, lungs/heart/ kidneys etc.., for knockout.
Many of the old style hand configurations used in particular techniques allow for the application of knockouts or even worse bodily damage, just by activating pressure points. Normally, we feel the pain of two pressure points in techniques, which is perfectly safe.
In case you are not familiar with this, there are many good references to help you with this . You can start with accupressure, acccupoint studies, then move on to other physical applications found in many martial art studies .
As far as weird Aikido? Well, if it is effective, then it is not weird ... just another way to get there from here, isn't it?
I have trained in a number of grappling, and other MA than Aikido ... sometimes it makes me switch when I slip in a hand grab or redirection to something a little more aggressive than the gentle redirection of Aikido, looking weird. It is a tough habit to break.
If I was you, I would get what ever I could about your teachers studies, and do some research. There are so many books on the market that are close to studies of most teachers, it might be the key to rethinking and relearning some different stratigy you are overlooking.
Classic Budo training doesn't always reveal its secrets without study. It took pressure point study, for me, to see that Aikido was so much more than the physical movements that work so beautifully.