Whilst it won't change the direction of the grain it will certainly change the colour - have you never sanded something? It takes off a layer of the surface, if that layer is a different colour from the underlying material then the appearance will be changed by the sanding process.
With regards to the grain that's inline with the long axis of the blocks, it's unavoidable that they will therefore be at 90 degrees to one another due to the herringbone pattern.
Yes, lots of things unfortunately. It will change the colour but not the inherent colour of the wood. If it's all the same colour underneath though that's fine.
Don't get me wrong, I'd do it the same way as you and I think it will look good.
Whilst it won't change the direction of the grain it will certainly change the colour - have you never sanded something? It takes off a layer of the surface, if that layer is a different colour from the underlying material then the appearance will be changed by the sanding process.
With regards to the grain that's inline with the long axis of the blocks, it's unavoidable that they will therefore be at 90 degrees to one another due to the herringbone pattern.