Couple of thoughts ..
(a) one significant risk is loss of horizontal tail surface forces resulting in a nose down pitch .. might not be a good idea coming over the fence if one is slipping aggressively. ie probably a good idea to heed the OEM's warnings and/or know one's aircraft's characteristics in some detail
(b) re IAS errors, I would be more concerned with the effect on static errors (PEC), especially for aircraft with static sources on the keel surfaces
Having said that .. it is a wonderful sensation to fly an approach to a spot landing in an aircraft which can do these things .. SuperCubs forever ...