Exactly, grumpy. That was the intention!
It's apparent that this clutch has had a fully or partially seized thrust bearing, in the hands of a 'previous tenant'.
And that this seized bearing has worn metal off the clutch disc surface that contacts its inner race. The previous repairer had only replaced the bearing, without attending to the disc damage.
The shim washer is the [perfectly valid, may I add] cheapskate way of remedying that damage, to restore full clutch function.
