More recently, a number of novel insertionbased architectures have been developed for sequence generation (Gu et al., 2019;<cite> Stern et al., 2019</cite>; Welleck et al., 2019) . These frameworks license a diverse set of generation orders, including uniform (Welleck et al., 2019) , random (Gu et al., 2019) , or balanced binary trees <cite>(Stern et al., 2019)</cite> . Some of them also match the quality of state-of-the-art left-to-right models <cite>(Stern et al., 2019)</cite> .