Deleting bulk records with pipeline

By coincidence I had an opportunity to want to purge child records when a parent was deleted. I used the remove record step and based on the timestamp of the pipeline steps, the pipeline triggered and then one second later 608 children were deleted.  

I found that feature and have cautiously tried it (first in a test table of course). It seems to work using the same syntax as a formula query. It zapped all my records (thank goodness the correct ones) very quickly. Only thing I found is the pipeline never says 'pipeline finished', so i am having customer service look at that part. It instantly works as expected, then just spins...and never says finished. I am trying to find out if that is taking up any resources. 

I can't help but laugh a little at your scenario. I once deleted a table by messing up an automation, but instead of zapping instantaneously, every time I refreshed the page less records where there. After about 100 deleted records my mind understood what was happening (my mistake in my filter) and I was screaming at the computer 'STOP AUTOMATION PLEASE STOP'. Needless to say, the automation did not stop.