All of my leftist followers should read these articles by Jehu - It's about the working day, stupid! https://therealmovement.wordpress.com/2017/11/14/according-to-the-central-intelligence-agency-we-almost-reached-communism-by-1980/amp/?__twitter_impression=true
To spell it out: crisis in the USSR was from over-investment in producing more and more capital goods in the hope to increase productivity. Enterprises refused to utilize these goods to increase output because of the ratcheting effect inducing them to hoard labor & other inputs
Had their labor budgets been radically reduced, they would have been forced to actually utilize these capital goods to increase production. In such a situation, planners could have allocated more resources towards consumption goods, and we wouldn't have seen such big shortages
Planners may have had a big incentive to increase productivity, but managers, which benefited big time from hoarding these resources and would later form the basis for the new oligarch class, did not, and were likely behind this retreat for shorter working days