Benoit wrote: "The final question is whether the Silver Arrows actually want to revert to such a dangerous rival as McLaren?
"For Sauber, the outcome really does not matter, as they will remain Honda's number 2 team next year," he added.
Meanwhile, although attending Le Mans to oversee his own team United Autosports, McLaren executive Zak Brown's presence at the fabled sports car race at the weekend turned heads.
"I'm sure Fernando is going to race at Le Mans one day," Le Mans legend Tom Kristensen said.
Another rumour is that F1 CEO Chase Carey and FIA president Jean Todt may have had talks at the weekend about wooing Le Mans competitors Porsche and Toyota to F1 for the new 2021 engine formula.
McLaren's Boullier said at Le Mans: "We are a great technology company, so why not offer our services to Le Mans participants, not necessarily as a competitor?"
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