Nil rate band clause and business assets

I am administering the estate of a deceased who holds assets which qualify for Business Relief. Attached is an excerpt from the clause titled DISCRETIONARY FUND OF NIL RATE BAND

IN the event that my Wife shall not survive me by six months I GIVE and without recourse to the property (if any) given by Clauses 3 and 4 of this my Will free of tax to my Trustees an amount equal to the largest sum of cash which could be given on the trusts of this clause without any inheritance tax becoming due in respect of the transfer of value of my estate which I am deemed to make immediately before my death and on the basis that recourse shall be had first to property (if any) comprised in my estate in respect of which a reduction of less than one hundred percent shall be made from any transfer of value comprising such property pursuant to section 104 of Inheritance Tax Act 1984 or any statutory re-enactment or modification thereof for the time being in force UPON TRUST on and subject to the trusts powers and provisions declared in this clause

Am I correct that this clause is sufficient to capture the Business Assets as well as the nil rate band? There are differing opinions on this so would welcome some comment from the forumn