Complex sentence: It is argued that the line's reopening would provide an alternative route to Plymouth and the Cornish Main Line in the event of engineering work or storms on the sea wall near Dawlish, although this would entail a reversal at Plymouth for trains continuing to Cornwall.
Split into simpler sentences: It is argued that the line's reopening would provide an alternative route to Plymouth and the Cornish Main Line in the event of engineering work or storms on the sea wall near Dawlish. This would however entail a reversal at Plymouth for trains continuing to Cornwall.