It is improbable, but there are many reasons why a specific 8700 might outperform a specific 8700k. There is a factor luck of the draw involved in the specific chips they test with.
I think it is more likely to just be testing margin of error
When the demand for the i7 920 was way up, there were a bunch of better chips sold as such.
Savvy overclockers knew which batch numbers they were and sought the particular runs.