I once had a Rolleiflex with the f3.5 Xenotar lens, and it was not especially sharp. My Rokkor lens on the Autocord is sharper. I sold the Rolleiflex.
Condition is everything. You probably had a faulty or malfunctioning Rolleiflex. So many knackered samples about, sadly.
I own several TLRs, with the following 4 in heavy rotation: an Autocord, two xenar Rolleicords, a Rolleiflex 3.5F Planar. All CLAd, all in as new condition. Additionally, the 3.5 F was entirely rebuilt and recalibrated by the Rolleiflex guru, Magicflex.
My Autocord takes pictures that are indistinguishable from those of my Rolleicord Va and Vb (not better, not worse: indistinguishable) and my 6-element Planar 3.5F at f/11 or smaller.
However, f/5.6-f/8, the fully CLAd Rolleiflex is noticeably different (some would say 'sharper'? 'better'? I'll go with different) than the Rolleicords and the Autocord. At 3.5, my 3.5F is a world away from the Autocord and Rolleicords.
I'm not dissing the Autocord/Rolleicords: in fact my Va is my favourite camera of all times: light as a feather, amazing lens, robust and quiet.
Also, it should be noted that the Autocord (as much as I love mine, I've taken some of my all time favourite pictures with it) is much more fragile than the Rolleiflex, and more 'pedestrian' in build quality.
I know people really love their Autocords - the camera is a legend and deserves the accolades - but a well calibrated 3.5 Planar/Xenotar is something else.