Originally Posted by CanAutM3
Up-shifting or down-shifting, there is similar amount of clutch slip (assuming similar shift times). However, on a full throttle upshift, there is much more force (torque) transmitted through the clutch, hence more wear.
It appears to me that a high rpm shift in say in S5 or S6 would have minimal clutch slip (less wear on the clutch disc), but would be harsher on the drivetrain in general
Being stuck in traffic and slow shifts in lower modes would have more clutch slip and wear on the discs. Other than launch control, high rpm shifts in S1-S2 (maybe auto mode too) should have the most slip and wear on the clutch discs.