Complex sentence: This caused Crass to fundamentally question their approach to making records, for as a group whose very reason for existing was to comment on political issues, they felt they had been overtaken and made to appear redundant by real world events.
Split into simpler sentences: This caused Crass to fundamentally question their approach to making records. As a group whose very reason for existing was to comment on political issues, they felt they had been overtaken and made to appear redundant by real world events.