I was told that lower stances are for kihon and kata and in kumite i should use a higer stance but when i counterattack i should change to a good and deep stance, thus my puch is stronger. About being old style its not supposed to be exactly like that but i have a different point of view. Have you trained in a dojo afiliated to the wska? The shihan is Hitoshi Kasuya. When he came to give a 5days seminary i was the translator. Thus we spent a lot of time together (every day from 6 am to 10 pm). He told me that although JKa still uses very deep stances, he prefers to use a low stance but not so deep, and the make the stances shorter and the purpose was to prevent damage the knee (and the typical knee surgery that a lot of karateka have). When i was preparing to my shoa test my sensei (who was recently affiliated with him) told me to do that thing with the stances and i didn't know why, i believed it was just to practice a little more of speed. But 4 days after my test when i was speaking with Kasuya sensei he told me about it. I even in my test he asked me to make my stances shorter although deep, resulting in a stance a little higher than the usual shotokan people.