Yes, it is too large. 4-0 or smaller is more reasonable. However, it would not cause or even significantly contribute to a CES.
However, I have seen a case in the last year that was "minimally invasive" that resulted in a CES.
The patient has surgery in the big city and returns home to the boondocks. The next morning he has complete, bilateral foot drop. The new MRI shows severe stenosis in the lumbar region.
We get the patient to surgery and the facet joints are trashed and undercut at more that one level (not good for stabilty). We do a traditional laminectomy and find a huge amount of fat graft, Gelfoam and Tisseal that are causing the stenosis.
There was also a tear in the dura with a fascicle of nerve that had herniated out.
Post-op the patient remembered that the surgeon mentioned some sort of a leak.
Foot drop is slowly improving.