Moreover, we demonstrate that the cyclobutene pendants of p(TCND)s can be excellent substrates for conjugate addition reactions with thiol nucleophiles (i.e., "thiol-Michael-type additions"), offering a straightforward methodology for efficient post-polymerization modification without the need for protecting groups or monomer activation (e.g., activated esters). These studies demonstrate that TCNs and TCNDs are attractive next-generation monomers for ROMP as (a) they are easy to synthesize in high stereochemical purity in as few as two simple steps from commercial starting materials; (b) they display propagation kinetics similar to or faster than many typical exo-NBs; and (c) they offer facile routes to postpolymerization modification that are not possible for common exo-NBs. Finally, this study presents the first application of computed steric parameters to correlate monomer structure with propagation rates in ROMP, providing insights into the predictive design of future ROMP monomers.