Functionality is a plus,
but - like i said - it just is not mentioned in the docs
and the app behaved a little weird - till i saw the "added bonus" in debuger,
since - depends how app is written(IsStoring/IsLoading may be used for some hokusPokus) - that
IsStoring/IsLoading may affect all later if/else/etc doings.

If app uses those two calls in Loading state of an app:
App must then not depend on that calls too much(once IsStoring will ret true and another IsLoading will also ret true),
so if app makes some hokus-pokus(mostly usually meaning app is not written correctly) - it must use it's own logic(it's own IsLoading/IsStoring).
That is not much of a problem though.

When user knows that there is a hidden backup(plus),
that makes a whole different story.

For upp this is mostly not a problem since source is there:),
but for closed-software that bonus not being mentioned could be an issue.

"(Actually, if you do not want the functionaly that Load provides, what is point of using it? Just create read stream and invoke Serialize)."
For convenience, instead of making 2/3lines - there is one.