replaced along with the water pump about 3-4 years ago. I thought this was NOT a thing to worry about.

You know, warm weather, going on I-95 doing an "italian tune-up".

.
The temperature now is between 80-85 degrees, as a matter of fact, it never went up more than 90 degrees. Even when I had to stop for the warning low coolant light on. I have not noticed any difference in the driveability of the car. Should I?
Could a bad auxiliary water pump cause this problem, if any?
I will definetely keep an eye on the temperature for a while, may be I am just lucky...I hope.