Complex sentence: In theory, both Collins and Mulcahy were responsible to Cathal Brugha, the Dáil's Minister of Defence but in practice, Brugha had only a supervisory role, recommending or objecting to specific actions.
Split into simpler sentences: In theory, both Collins and Mulcahy were responsible to Cathal Brugha, the Dáil's Minister of Defence. However, in practice, Brugha had only a supervisory role, recommending or objecting to specific actions.