can.compute-friendly validations

[daffl]

https://github.com/bitovi/canjs/blob/master/observe/validations/validations.js#L376 shows:

var res = func.call(self, isTest ? ( self.__convert ?
   self.__convert(attr, newVal) :
   newVal ) : self[attr]);

If self[attr] became self.attr(attr), it would allow can.computes to be constructed on can.Observes based on validations. Would this cause undesirable side effects?