thats anxiety thats causing that.
lurchers can become very timid especially if they were mistreated.
ive got one and he's similar, he got run over so now he's a nervous wreck. go to take the rubbish out and when you come back in its like he aint seen me in 3 year
we recently got an alsation and she's toughened him right up, we think he's just acting it coz he wants his hole but he's no where near as bad now.
im no expert on how to train em out of it but it is possible.
good luck. cracking dogs lurchers especially when their chasing rabbits. mines only got 3 legs so he's fast in a straight line and barrell rolls if he tries to turn too fast!