SuperLoop shape Discrepancies

After ingesting the shape data for the Superloop (Specifically SL7), I have noticed some anomalies with the shape points within the data. These anomalies are causing the shape towards the Heathrow end of the line to show as the crow flies, rather than following the curvature of the road as would be expected.

I have noted similar issues for line 344 also. I was wondering if anyone has noticed similar instances?

Is this not due to it being a limited stop service?