Ludwig - your post is interesting in that yes, that is exactly how every instructor I've flown with has initiated a spin (control yoke hard into chest and full rudder). I always presumed this was just to ensure clean entry into a "proper" spin, which is pretty important on Cessnas where you could just end up wallowing around in a half arsed spiral.
I remember once during spin demonstration on a 172 my instructor even found it necessary to blast the rudder with full throttle to get the thing to spin at all.
Have since spun C150s and C172s but the Tomahawk is certainly the best spin trainer I've flown in. Easy, positive initiation and recovery.
As regards the spin itself, I must say I didn't enjoy it that much as a passenger first time out, but when you have the controls yourself it really is great fun, and a much gentler manoeuvre than a spiral dive.