Belt-drive, no. This was early in the direct-drive era (and I think 2-speed, not 3-speed with the ex-low agitation choice?), thus Bob's naming it The Lady Shredmore. WP had belt-drive until sometime in 1986 but KM probably changed all models to DD before WP.
Did Kenmore have any models with step-down agitation, à la Whirlpool's "Gentle Wash System?" The 1999 KM 90 I have doesn't do that, agitation is at the selected speed for the duration of the cycle.