Here is the Nascar reason for the 20 minute competition cautions in Truck. I think the part I bolded says why Cup drivers shouldn't be racing trucks. I'm pretty sure O'Donnell said that Trucks is a developmental series for young drivers. The underlined is simply a good question.
Clock will mandate competition cautions
NASCAR will display “competition cautions” every 20 minutes during its
Camping World Truck Series races this year in an effort to help younger, less experienced crews and drivers learn to make race-truck adjustments on the fly. The new procedure was unveiled on Tuesday during the Charlotte Motor Speedway’s annual Media Tour.
As outlined by NASCAR executive Steve O’Donnell, a “caution clock” will count down from 20:00 as teams take the green flag to start each race. If a caution doesn’t occur naturally by 00:00 on the clock, NASCAR will display the yellow caution flag and teams will pit as they always have. The clock will be reset to 20:00 when the race begins, and again count down to 00:00 -- barring another “natural” caution. The 20-minute intervals will continue with every restart until the race “window” is clearly inside 20 minutes.
T
he obvious question to O’Donnell was, why? After all, for years fans have been quick to claim NASCAR uses bogus cautions to keep fields tight or create late-race dramatics. Suddenly, those fans are going to give NASCAR a pass for displaying cautions for no reason whatsoever?
“We think it’ll add to the strategy during the race,” O’Donnell said. “If you look at the Camping World Truck Series, that’s an area where some of our younger drivers and younger teams and newer teams can use the competition caution to adjust on the truck. We’ve seen that in the Cup Series when, we’ve had a competition caution early in the race, it’s allowed teams to make some last minute adjustments early in the race.
“We think it’s going to be huge for the truck teams throughout the race. It’ll be implemented throughout the season.”