Data shows a clear example
FE Hoppy - thanks for the document you linked. Page 24 therein clearly shows a lift curve that shifts down/right as slats that extend forward and downward are deployed. For such a wing as that one extending the slats will lead to a higher pitch attitude at the same speed. As you make clear this is for a failure condition where slats are deploying without trailing edge flaps. We are much more familiar with flaps and slats extending in concert yielding a higher Cl and thus a lower pitch attitude.
For this failure case it might be possible to take advantage of the slats alone to permit a slower approach speed but that could yield a high enough pitch attitude to risk tail strike. As so often is the case the devil is in the details.