Option Debug "use gpu texture scaling" optimize cpu usage ?

Hello.
All good with you ?
In Settings \ Debug have the option "Use GPU Texture Scaling".
That move scaling and convertion to gpu.
For an user is as if the processing is being moved from cpu to gpu and thus the cpu have more free usage to others tasks.
Thus the user think in enable it.

However if enabling it not really move processing from cpu to gpu not optimizing peformance not is correct enable it.
Why has that option ? help in debug ?

Thanks for reading my topic.