Opus 4.7 vs GLM 5.1: is mixing models worth it?

A couple of months ago, I compared Opus vs GLM by having both of them do a task for me. It’s not that surprising that Opus was best. But what if we get both cooperating? For optimization purposes: one planning, the other executing. I ran this comparison before, same plugin ( cm-multilingual ), three runs: Opus 4.7 alone, GLM 5.1 alone via Ollama Cloud, and GLM 5.1 following the plan Opus had written. It was a small task – just providing progress feedback for the AI translation – and the "cheap f