2.5mg Letrozole vs 5mg Letrozole

Did anyone ovulate on 2.5 mg letrozole but not conceive until their dose was bumped to 5mg? I've ovulated on 2.5mg three times (3rd time being currently) with gyno and fertility doc is bumping me to 5mg next cycle. He said bumping the dose may help "tighten things up" whatever that means lol. Wondering if this made a difference for anyone even if they were ovulating on the lower dose.