If I use the Pot Scrubber cycle, (remember when it was called Super Scour?) I select high temp wash because the first wash period in Pot Scrubber washes until the water reaches 145F. Even when I draw 140F water up to the kitchen faucet, that first wash lasts around 50 minutes. Though I insulated my hot water pipes, the water cools off during this time so the fill for the rinse between the washes is kinda cool and the fill for the second wash, while close to 140 is going into a cooled tank. Using the high temp wash guarantees a 145F wash as well as giving extra scrubbing time during the water heating. If things in the load do not merit the Pot Scrubber cycle, the additional wash time provided by the heating delay when High Temp Wash is selected is usually sufficient to remove heavier than usual soil.
Incidentally, John found that higher rail around the lower rack actually reduced capacity when it interferes with placing large items like pots and mixing bowls that would have rested against the top of the lower rail and leaned outward to use that fraction of an inch above it in the previous rack design, but are forced to sit more inside by the high rail.