  Whilst discussion has continued on the relative merits of the choice and benefit theories, and ever more sophisticated versions of each have been proposed (see, for example, the three-sided debate in Kramer, Simmonds and Steiner 1998, Kramer 2010, Vrousalis 2010, Van Duffel 2012), some writers have attempted to offer different, or combined, approaches.  Wenar (2005) argues for what he calls a ‘several functions’ theory.  According to this, any ‘Hohfeldian incident’ (or combination of them) which grants exemption, discretion or authorisation, or entitles the holder to protection, provision or performance is a right.  Kramer and Steiner (2007) claim, however, that this is really no more than another version of benefit theory, and not superior to existing ones.  Another proposal is made by Sreenivasan (2005), which is intended to apply only to claim-rights and not to other varieties of right.  The essence of it is that Y has a claim-right that X perform an action if and only if Y’s measure of control over X’s duty matches (by design) the measure of control that advances Y’s interests on balance.  This, too, is criticised by Kramer and Steiner (2007) on the basis that it would include the case in which someone has, on the basis of his own interests, deliberately not been granted any such power at all.  Yet this, they claim, would lead to a highly implausible expansion of the class of those who would have to be regarded as right-holders.