I see the things as you mention. I can not see frictionless as a code requirement, more over the para.319.4.3 specify that restraint introduced by
support friction, shall be recognized (I see here that you may say you can take credit and none should say no you can't). I think that however, one may say that us as engineers, need also to see that friction is transitory in nature and we should not take credit from friction. In addition, if client ask to consider also the frictionless, well this is an additional requirement, that not negotiated at bid phase will bring some extra headache.