ProxyStore.isLoaded - not robust enough?

I'm curious why the isLoaded method checks loadCount and not the length of data which IMO would be more robust.

It's possible for a store to contain data and have the loadCount equal zero for example by calling store.add on an empty store.

Code:

Ext.define('Ext.data.ProxyStore', {
    extend: 'Ext.data.AbstractStore',
    ...
    /**
     * Returns `true` if the Store has been loaded.
     * @return {Boolean} `true` if the Store has been loaded.
     */
    isLoaded: function() {
        // return this.loadCount > 0;
        return this.data.length > 0
    },
    ...

ProxyStore.isLoaded - not robust enough?