Sadayo was active in the poetic disputes of that day, scoring a signal victory over the Nijō adherents close to the Ashikaga Shogunate at the time with 6 polemical treatises on poetry he wrote between 1403 and 1412, defending the Reizei's poetic doctrine and their cause (despite Ryōshun's renga poetry's debt to Nijō Yoshimoto's (1320–1388) examples and rules of composition). Ryōshun used a number of quotations to bolster his case, including notably a quote of Fujiwara no Teika's, which was that all of the "ten styles" (Teika had defined ten orthodox poetic styles, such as "yoen", a style concerned with "ethereal beauty", "yūgen", the demon-quelling style, or the one the Nijo championed to the exclusion of the other 9, "ushin") were licit for poetic use and experimentation, and not merely the Nijō's "ushin". With the aid Ryōshun afforded him, Fujiwara no Tanemasa's politicking eventually succeeded in converting the Shogun, ending the matter- until the rival Asukai poetic clan revived the dispute, that is.