Binary option for vtk surface format

In my understanding, there is no option to write surfaces from functionObjects, e.g. iso-surfaces, in a binary vtk format.

I believe this would be quite useful to reduce the size of each single file and speed up the reading in Paraview. For example, the iso-surface of Lambda2 in a 10M cells mesh from an external aero application is as big as 500M and it takes more than 10 seconds to be read.

Would this be possible or is there any constraint regarding the vtk format preventing this option to be implemented?

Thanks,

Riccardo