What? Of course they can pull it off. Hell,
I could pull it off. It is just data manipulation. Most RTS's already keep track of this stuff in order to record replays, it makes sense that they take it one step further and allow for real time manipulation of those replays. After that it is handling all the edge cases (time paradoxes).
Seriously, technology wise, its nothing revolutionary. The only thing revolutionary is the application.
Strategy wise, it comes down to out thinking your opponent. So what if the nuke lands just move your units in the past. But your Opponent may have anticipated this and already set in motion another set of changes. The trick isn't simply to beat every enemy unit but to trap all those units in an unwinnable situation. Its more like chess in a way. Besides, its not unlimited time travel. There is a set cost, and if you are in a situation where the only way to rectify it is to go far back in time, you just may not have enough
CHRONOTONS
... to get the job done.