Okay so you still have a little way to go towards understanding how all this works... The PREs begin to occur when you or one of your scripts begin to access MTurk faster than once time every 1 second. PANDA Crazy is designed to automatically prevent PREs from occurring so it will regulate itself to access MTurk only once every 1 second, and PREs will only occur if you change the timing of PANDA Crazy to run faster than once every 1 second or you doing something else like you rapidly complete a bunch of 1-click HITs (A9s) while PANDA Crazy is simultaneously running PANDAs.
Anyyway, the point is if you have 10 PANDAs running at the same time, then PANDA Crazy will not be checking for all 10 of those HITs every 1 second. Instead PANDA Crazy is going to check for the 1st HIT that you've PANDA'ed, and then wait 1 second before it checks for the 2nd HIT you have PANDA'ed, and then wait another second before it checks for the 3rd HIT that you've PANDA'ed...
So essentially, when you are running 10 PANDAs at the same time, PANDA Crazy is only able to check for each of those HITs once every 10 seconds!
So imagine that I have accepted a $10 HIT that you really, really want to catch so you have a PANDA running for it. Now imagine that I have run out of time and need to let the HIT expire. When I return the HIT, it is available again and you are already running a PANDA to catch it...
...but you're not the only one running a PANDA for the same HIT. Imagine 1 other person is trying to catch the HIT at the same time and they have a PANDA running. This is the only PANDA that they are running, but you are running this PANDA and 9 other PANDAs at the same time.
Since your PANDA for this HIT is only able to try to catch it once every 10 seconds, then the other person will catch this HIT instead of you.
Now imagine if the $10 HIT expires from my queue and is returned at 12:51:07PM, then the timing will work out like this:
12:51:00PM - Other Person's PANDA for $10 HIT - Your PANDA for $10 HIT
12:51:01PM - Other Person's PANDA for $10 HIT - Your PANDA for other HIT #2
12:51:02PM - Other Person's PANDA for $10 HIT - Your PANDA for other HIT #3
12:51:03PM - Other Person's PANDA for $10 HIT - Your PANDA for other HIT #4
12:51:04PM - Other Person's PANDA for $10 HIT - Your PANDA for other HIT #5
12:51:05PM - Other Person's PANDA for $10 HIT - Your PANDA for other HIT #6
12:51:06PM - Other Person's PANDA for $10 HIT - Your PANDA for other HIT #7
12:51:07PM - Other Person's PANDA for $10 HIT - Your PANDA for other HIT #8 - I return $10 HIT now
12:51:08PM - Other Person's PANDA for $10 HIT - Your PANDA for other HIT #9
12:51:09PM - Other Person's PANDA for $10 HIT - Your PANDA for other HIT #10
12:51:10PM - Other Person's PANDA for $10 HIT - Your PANDA for $10 HIT
12:51:11PM - Other Person's PANDA for $10 HIT - Your PANDA for other HIT #2
12:51:12PM - Other Person's PANDA for $10 HIT - Your PANDA for other HIT #3
12:51:13PM - Other Person's PANDA for $10 HIT - Your PANDA for other HIT #4
12:51:14PM - Other Person's PANDA for $10 HIT - Your PANDA for other HIT #5
12:51:15PM - Other Person's PANDA for $10 HIT - Your PANDA for other HIT #6
12:51:16PM - Other Person's PANDA for $10 HIT - Your PANDA for other HIT #7
12:51:17PM - Other Person's PANDA for $10 HIT - Your PANDA for other HIT #8
12:51:18PM - Other Person's PANDA for $10 HIT - Your PANDA for other HIT #9
12:51:19PM - Other Person's PANDA for $10 HIT - Your PANDA for other HIT #10
12:51:20PM - Other Person's PANDA for $10 HIT - Your PANDA for $10 HIT
12:51:21PM - Other Person's PANDA for $10 HIT - Your PANDA for other HIT #2
12:51:22PM - Other Person's PANDA for $10 HIT - Your PANDA for other HIT #3
12:51:23PM - Other Person's PANDA for $10 HIT - Your PANDA for other HIT #4
etc...
I really really hope that makes sense to you why running too many PANDAs at once really puts you at a disadvantage when trying to compete with other Turkers when trying to catch HITs.