Let me give a simpler explanation. At night, go into an empty field with no nearby objects that would get in your peripheral vision when you look straight up. Note the pattern of the stars. Walk 20 paces to the left and look up again. Any change? Now walk 30 paces forward and look up. Still no change? When you are talking about celestial distances, there is very little change when you move so little. Even when our planet is on the opposite side of the sun (half a year from the observation date), the pattern of stars remains unchanged to the naked eye, and only fine instruments can detect the minuscule differences in their relative positions. Since those lines in hyperspace are created by stars, there is really no change no matter where on the ship you sit.