AI & ML Breaks Assumption

Reveals that complex reasoning strategies like Chain-of-Thought (CoT) and Tree-of-Thought (ToT) provide negligible or even negative gains for text classification tasks.

March 23, 2026

Original Paper

TextReasoningBench: Does Reasoning Really Improve Text Classification in Large Language Models?

Xinyu Guo, Yazhou Zhang, Jing Qin

arXiv · 2603.19558

The Takeaway

Practitioners often blindly apply CoT to increase performance across all tasks. This paper empirically shows that for classification, the massive increase in token cost and latency does not justify the minimal (1-3%) accuracy gains, advocating for simpler decoding strategies.

From the abstract

Eliciting explicit, step-by-step reasoning traces from large language models (LLMs) has emerged as a dominant paradigm for enhancing model capabilities. Although such reasoning strategies were originally designed for problems requiring explicit multi-step reasoning, they have increasingly been applied to a broad range of NLP tasks. This expansion implicitly assumes that deliberative reasoning uniformly benefits heterogeneous tasks. However, whether such reasoning mechanisms truly benefit classif