Lil: Less is Less When Applying Post-Training Sparse-Attention Algorithms in Long-Decode Stage. - Junhao Hu; Fangze Li; Mingtao Xu; Feifan Meng; Shiju Zhao; Tiancheng Hu; Ting Peng; Anmin Liu; Wenrui Huang; Chenxu Liu; Ziyue Hua; Tao Xie 001 (CoRR, 2026)