Is this typical?
Not from my experience.
Tomiki Shihan utilized Kano's educational and structured approach towards how he developed Aikido but was adamant to keep the two arts separate.
This site can give much more information and probably add some clarity to things - http://homepage2.nifty.com/shodokan/en/index.html
it gives a detailed historical account of the idea behind Shodokan Aikido and why it was developed to be the way it is.
Alternatively I must add that there are Tomiki Aikido groups in existence that do not follow the Shodokan method per se. Does your dojo have a website? The governing body for Shodokan in the U.S. is the J.A.A./U.S.A. in which case your dojo should be listed on this site somewhere - www.tomiki.org