someone from SMS added this to the EG comments if anyone is interested:
"Just to add to our previous comments:
- In the older build that was analysed it was possible to become CPU bound with very high numbers of AI, maxing out all 6 cores on XBox One. However, Microsoft had recently opened up 50% of the 7th core to developers : in later builds the development team was able to offload work such as the audio mixing, engine sound synthesis and detailed grass generation onto this core, fixing this problem of becoming CPU limited.
- Tracks that had water elements (sea/lakes etc) in the analysed build used an expensive cube-map method for reflections leading to inconsistent frame rate. In late March this was addressed with us switching over to use a screen space reflections method - A WMD community member did some comparison benchmarks on PC when this new technique was introduced:
"B967/B968
Azure Coast 62.5 fps/82 fps +31%
Azure Circuit 61.5 fps/ 73 fps +19%
Laguna Seca 55 fps/76 fps +38%
Sakitto GP 61.5 fps/86.5 fps +41%
Nürburgring GP 57.5 fps/76.5 fps +33%
Looks identical visually, big improvement."
The relative scaling there applied equally to the console versions.
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If you incorporate our above corrections to the article, these points and some more general optimisations that have subsequently been worked on, it's easy to see why we might feel this review isn't very representative of what the development team has achieved."
sounds like SMS are happy with what they've achieved and come May 8th i'm sure i will be too!