linguistics strikes twice

Once, my mom and I were home during a terrible lightning storm. I had to pee but was afraid to be on the toilet, near water, in case lightning struck the house. I conveyed my concerns to mom, who said, "Well, just go really quast."

What mom did was manage to speak a combination of "quick" and "fast."
My mom was cute when she did something like that. She would get this look where she was just barely trying to hold back laughing. She was maybe a little embarrassed, but not very.

Another time, my cousin Dina was talking about a family gathering, to take place in the near future, that would consist of going to another relative's house to eat food outside. She wanted to know if I was going to attend and asked, "Are you going to the pic out?" We both cracked up after she said it.

I wonder what in our brains causes us to mix two words like that.
In a way, it is impressive if you can process two synonyms and then actually find a way to speak both of them at once in an unintended combination. One could argue that it is a form of superior intelligence because it indicates that in a split second you can think of more than one way to say something without even trying. Maybe that trait is more desirable than constantly needing to search for the right words.

In any case, I suspect it indicates you're more intelligent than someone who worries about being on a toilet for 12 seconds during a lightning storm.