(2) Re-expression of the doctrine: If it is concluded that the defects in the extended common purpose doctrine are such as to justify, and require, a re-expression by this Court of the applicable rule of the common law, should the re-expression state that to secure convictions of co-accused on the basis of an alleged common purpose, the prosecution must prove that the secondary offender, which it seeks to render liable equally with the principal offender, desired the latter to act with the intention that he or she did, or knew that it was "not merely a 'real possibility' [that the primary offender might do so] but virtually certain that he would do so"[69]? Or should any such statement render the secondary offender equally liable with the primary offender on the ground of extended common purpose with the primary offender, only if the prosecution proves that the secondary offender foresaw as a probability, in the carrying out of the agreed understanding or arrangement, that death or really serious injury would occur by the act of one of them[70]?