On a "real" hit, hit points are subtracted.
If we look at an attack as an attempt to reduce hit points, and a healing surge as an attempt to increase hit points, then a miss can be a hit + a healing surge.
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Yes, I'm grateful to WOTC for greatly simplifying combat and making it all so much easier to explain to new players.
If you're offended by my sarcasm, I suggest you read the last phrase of the quoted passage five times fast.