What he classifies as "lying qualifiers" seem to me often just used to soften what follows the "but", and has become the standard: we are so much used to this t

What he classifies as "lying qualifiers" seem to me often just used to soften what follows the "but", and has become the standard: we are so much used to this that the impression it would make without these "softeners" would be of a rude remark. Although the message we want to convey, plainly and in all honesty, is "I think X", the standard approach is that we want to avoid giving this impression and say "I don't want to be rude, but I think X", whose effect on the other person is "I think X".