@Gargron The body design isn't a trick, you can shoot a 67 handheld -- I've handheld an RZ before and the Mamiya 7-II is made for street photography -- it's just not the same head math as small format because you can't use a shutter speed that matches your lens length any more. Like, you can't get away with 1/60s at 60mm. And the additional resolution is worth using as sharply as possible. Did those have FP or leaf shutters? May want to test accuracy after so many decades
@Gargron Like, 60mm for example is wider on a medium format, so you think it'd be easier to shoot slow, but IIRC the 67 had a focal plane shutter and big slappy mirror that will get the body moving pre-exposure and shake up your photos much more than a 35mm SLR. The Mamiya 7-II used leaf shutters and a rangefinder to eliminate this effect. You may need at least 1/125 to steady a wide angle on the 67