No Depth Perception??? Not so. Depth perception is more complicated then just stereo vision. The brain makes numerous calculations to gage distance based on past experience of object perception, shadows and reaching and targeting tasks.

The basic example is close one eye and walk around, you'll find that within your field of vision depth perception rarely cause any issues. Most errors come from the reduced field of vision and not loss of depth perception.

People who lose an eye after age 4-5 are able to compensate quite well and maintain depth perception as a result of developmental learning. Like any skill aspect if it practiced as part of training for a broader skill (ie sword fighting) a person can achieve near equal skill level to high level skill achievers.