This paper makes a proof-theoretic contribution to resource-bounded dialectical argumentation. Practical deployment of argumentation-based nonmonotonic reasoning can benefit from integration of proof-theoretic means for construction and evaluation of arguments, while accommodating agents with bounded resources. We present a nonmonotonic proof system that implements a generalization of dialectical argumentation, adopting arguments that differentiate between committed and supposed premises, while integrating rules for constructing arguments. The proof system adopts annotations to capture the changing status of arguments in a derivation and employs annotation revision rules that evaluate the dialectical acceptability of these arguments, yielding rational outcomes under resource bounds. Soundness and completeness is shown for the dialectical grounded semantics.