I honestly don't know much about jidwaaq other than the fact they're darood like gerrikombe.
as far as arsi and somali relations go, they are too complex.
they've been allies at times, and also foes recently as when abdi illey's mercenaries were raiding arsi, hararghe, guji, etc, and killing them for the sake of their tigrayan elitist masters.
This book deals with the dimensions of ethnicity and ethnic interaction in Northeast Africa. It proposes a mechanism to establish a condition of peaceful co-existence among ethnic groups in the region.Contents: List of Tables and Diagrams; Foreword; Preface; Acknowledgements; Language and...
books.google.com
here's a good read!