Chapter 6 revisits the grammatical asymmetry, a key effect in agreement attraction research. The grammatical asymmetry refers to the phenomenon where attraction effects occur in ungrammatical sentences but not in grammatical ones. This chapter evaluates existing evidence, particularly in response to challenges raised by Hammerly et al. (2019), who claimed that the empirical evidence for the asymmetry is not particularly strong and that the effect could be a product of response bias rather than an inherent property of agreement attraction. Through a detailed review of over ninety experiments, the chapter finds strong support for a grammatical asymmetry, as predicted by the retrieval-based account. Additionally, it explores how altering the ratio of ungrammatical to grammatical fillers in experiments can influence retrieval mechanisms and artificially produce a symmetrical attraction profile, yielding the response bias effect observed by Hammerly et al. These findings suggest that a symmetrical profile could emerge from increased uncertainty in memory retrieval rather than faulty linguistic representations, offering a nuanced interpretation of existing behavioral findings.