E10 petrol

Somebody wrote about a fortnight ago enquiring about E10 petrol?. As I
mentioned I had just filled up with the stuff. For 3 days it seemed fine,
may be imagination/placebo effect but T3 did seem to be smoother. After 3
days car periodically acted as if there was dirt in a carby( definitely only
one working, made driving in peak hour Sydney traffic real fun -NOT). ran
the thing down to almost empty then refilled it , no problems, back to
square one!.
Coincidental?, maybe but I wouldnt bother with E10 again.
John