In terms of constitutional amendments floor crossing was promulgated as a full blown Act. In most cases this will entail a minor amendment which is not considered as a Constitutional change. There are several of these types, but the Act itself doesn't amend the constitution, however it may have demanded slight changes to wordings, or have additional paragraphs added that clarifies existing sections or paragraphs. In such instances it is accepted that such additions are not classified as amendments.
Obviously, like most things in legal considerations, this more about semantics. In my personal opinion, I think such wording is particularly used so as to create the impression that the constitution is not actually being amended, though clearly the Act(s) is/are being used to amend the definitions held in the constitution. But in terms of chapter amendments, an Act may under some circumstances imply amendments to the constitution, even though such Acts are not actually changing anything in the constitution. It can be quite confusing
There are several minor amendments which have led to Acts of Law, nonetheless these minor Amendments may well have altered the Constitution quite significantly.