The only way there won't be an increased load on the powertrain is if the revs are matched. If the revs are mis-matched then the transmission will be at a different point in the powerband (likely out of the powerband) and will result in increased loads experienced.
Right. Perhaps jamesjguthrie isn't seeing the difference between engine noise (mechanical strain), and engine load. "Engine load" is the additional force requested, which will be negative when the wheels are driving the engine. He's also including rev matching in a conversation that is not about clutch or torque converter wear, so there's definitely some confusion.
