can.compute-friendly validations

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