Why was Denny Hamlin allowed to go back out on track?

May be...

so he can get some points

i don't know either.. maybe it applies to cars that have been in wrecks only

I've never heard of that rule. As for as I know, cars have to maintain a minimum speed, and they did...the third time around.

I thought there was a rule that the crew had one chance to fix their car, and if the car can't go out and maintain minimum speed, then they don't get to go back and forth to the garage all day.

After he brought out the second caution flag, his day should have been over if NASCAR was interested in enforcing the rules.

What am I missing here?warpspeed y pipe