Before revision:  Up to 10th-order accuracy is demonstrated using Gauss integration , while in all cases 4th-order Gauss integration requires roughly half the number of preconditioner applications as required by standard SDIRK methods.
After revision:  Up to 10th-order accuracy is demonstrated using Gauss integration , while in all cases 4th-order Gauss IRK requires roughly half the number of preconditioner applications as required by standard SDIRK methods.