Wiktionary
walk and chew gum at the same time
vb. (context idiomatic informal English) To do two trivial tasks at the same time
Usage examples of "walk and chew gum at the same time".
It's too busy keeping us balanced as we walk, so we can walk and chew gum at the same time.
The OS is multi-threaded, which means that like all other modern OSes it can walk and chew gum at the same time.
But it was pretty obvious, now, that old PC operating systems were overreaching, and showing the strain, and, perhaps, were best avoided until they had learned to walk and chew gum at the same time.
Your normal animal, in fact, never tries to walk and chew gum at the same time.