Accurate modeling of small-scale redshift-space clustering is crucial for full-shape redshift-space distortion (RSD) analyses, where satellite galaxies contribute to one-halo terms and Finger-of-God distortions. We investigate halo reconstruction based on the cylinder grouping method of Okumura et al., Mon. Not. R. Astron. Soc. 469, 459 (2017), which selects an effective halo center tracer from the observed galaxy distribution, and how it impacts cosmological parameter inference. Using luminous red galaxy mock catalogs from the AbacusSummit simulations at $z=1.1$, we perform effective field theory (EFT)-based full-shape modeling of the power spectrum of the reconstructed-halo sample. We show that the dominant reconstruction-induced systematics can be described and incorporated within the standard EFT framework. In particular, a simple multipole-dependent rescaling inferred directly from the data on large scales captures the dominant effect, while residual small-scale changes are absorbed by the standard counterterm and stochastic sector, without introducing additional reconstruction-specific parameters. The reconstructed-halo sample yields unbiased constraints on cosmological parameters, including the growth rate $f{\sigma }_{s8}$ and Alcock-Paczynski parameters. Compared to the galaxy sample, it enables both improved robustness and increased statistical precision: at the fiducial limit of $k_{\max }=0.2h{\mathrm{Mpc}}^{-1}$, the uncertainty on $f{\sigma }_{s8}$ is reduced by more than 20%, while the high-$k_{\max }$ diagnostics show comparatively stable goodness of fit and nuisance parameters.

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• Cosmological parameters
• Large scale structure of the Universe
• Distances, redshifts, & velocities