nothing in Part III precludes an occupational pension scheme from providing benefits that are more favourable than those required for contracting-out purposes and, in particular, nothing in section 12(3) is to be taken as preventing the scheme from providing increases above the alternative minima there mentioned; and

nothing in the provisions of Chapter II or IV of Part IV precludes a scheme from being framed or managed more favourably to beneficiaries than is called for by those provisions.