The proposal by Clahsen and Felser (CF) has the potential of marking a turning point in second language (L2) acquisition research. Contrary to much L2 research to date, it suggests that some of the differences between native and (advanced) nonnative speakers may be at the level of grammatical processing, rather than grammatical representations. Accounting for L2 speakers' divergent behavior does therefore not necessarily involve positing “representational deficits”: L2 speakers can, and indeed do, attain target representations of the L2, but may compute incomplete (“shallow”) syntactic parses in comprehension. Such shallow processing is often accompanied by reliance (or overreliance) on lexical, semantic, and pragmatic information, which can lead to seemingly trouble-free comprehension in ordinary communication. It is only when speakers are faced with sentence ambiguities, which impose a greater than normal processing load, that the differences between adult L2 language acquirers and child first language (L1) acquirers become apparent: both child and adult language learners have difficulty in integrating structural and nonstructural information in on-line comprehension, but although children prioritize structural information, adult learners privilege nonstructural lexical–semantic information. CF's proposal opens up new perspectives on the nature of ultimate attainment in adult L2 acquisition; at the same time it raises some questions that, in my view, are of crucial importance for future research.