Nstra question

I have been reading the websites for the NSTRA events and have a couple of questions.



What is a dbl/dbl event?

Are training collars allowed during the event?

Does shooting accuracy count? Number of shots fired.

To enter as a amateur do you need to join NSTRA or just the entry fee?



Also maybe 15 years ago or so I use to participate in some events at hunting preserves where we did timed events. You had like 20 minutes and 3 birds were planted, your score was based on how much time was left, number of shells left (you were allowed like 6) birds had to be pointed and retrieved to within 1 step. Was this just a variation of STR fun event made up, or was it a actual type of trial that that was being done?



Thanks



Dan G