I wonder!...Assuming astronomers found a mountain-sized asteroid
tomorrow on target to hit the Earth just over 100 years from now.
Assuming you can modify the JIMO propulsion-system to approach, contact and temporarily anchor itself to that say, 4 billion ton asteroid,
couldn't that JIMO propulsion-system create a tiny but sufficient Delta-Vee for that asteroid to miss Earth in 100 years?

Say a Delta-Vee of maybe only a millimeter/second?

A millimeter/second would deflect the orbit of an asteroid by just a little under 87 meters (300 feet) per day; just over 30,000 meters per year;
3,000 kilometers (1800 miles) per century.

Jacob