Hope you used Overcast on 2x :)
But even on brazilian, humorous podcasts i dont speed up. I listen while doing chores and the ocasional commute. No hurry. I took about a month to finish this one.
Your english is very good! Congratulations!
It is better in written form. Two tips: always review it after writing and use Grammarly (https://www.grammarly.com/).
I can understand how keeping it at a normal rate is beneficial as deep as he goes on the material.
I've found the audio has to be clean and clear to take advantage of higher speeds of listening. Takes practice, but almost every podcast I enjoy I do 1.5x+.