Sure, but despite there being a 2.0 release between they didn't even feel the need to release a Pro for it still isn't the kind of GPT 2 -> 3 improvement we were hoping would continue for a bit longer. Companies will continue to release these incremental improvements which are all always neck-and-neck with each other. That's fine and good, just don't inherently expect the versioning to represent the same relative difference instead of the relative release increment.

I'd say 2.5 pro to 1.5 pro was a 3 -> 4 level improvement, but the problem is 1.5 pro wasn't state of the art when released, except for context length, and 2.5 wasn't that kind of improvement compared to the best open AI or Claude stuff that was available when it released.

1.5 pro was worse than original gpt4 on several coding things I tried head to head.