Why does jsvUnLock() not return the JsVar?

I am wondering if there was a reason that jsvUnLock() does not return the JsVar that it is unlocking?

If it did, it would seem to offer me a new way of coding. For example, today I have the option of coding:

JsVar *x = jsvNewFromInteger(10);
jsvUnLock(x);

while if jsvUnLock() returned its passed in JsVar, then I would appear to have the option:

JsVar *x = jsvUnLock(jsvNewFromInteger(10));