Hi Dejan,

Please consider that the Item Group (and similar the Schema for the field list) was originally introduced with the aim to save band, in the request sent from client to server, and time, to the client developers, in the cases where very long lists, even of several hundreds, of Items (or fields) were involved.
In those cases we assumed that the client was aware of the composition of the list, which was static, and could map internally the position returned in the updates with the actual Item.

However, in cases of dynamic lists, we are aware that the lack of meta-information on the actual composition of the lists is very annoying.
And that is why we are considering whether to add the feature in the future.

Regards,
Giuseppe