Yes thats right. Its a little trickier when he is moving backwards as it makes for more ground to make up. To set it up on the retreat without getting hit you must have a serious attack directed at him. Preferably one that has landed. For example, lets say you are sparring and working the other guys legs pretty good. He will take notice of this after a few shots and if he is trained well enough then he will do one of two things. He will raise the leg to absorb the blow or he will step back. If he is real good he will move forward but thats another discussion. Anyways, fake one, and when he goes to absorb the blow or to evade it, already have your mind made up to advance upon him. This works alot. Especially if he is taking the impact by raising his leg. Before he can move away from the blast he must put his foot back down. This is his mistake. Abuse it to destroy his balance or at least get a few solid shots in.
"When I let Go of who I am, I become who I might be."
Lao Tzu