Complex sentence: Harrop's writing is characterised by physicality and an increasing sureness of style, but also by a seriousness, a pained innocence, which when allied to his independent views may seem ungainly to some readers.
Split into simpler sentences: Harrop's writing is characterised by physicality and an increasing sureness of style. It has a seriousness, a pained innocence, which when allied to his independent views may seem ungainly to some readers.