It still happens in MPCE 0.12.3, although there is some improvement.
It seems that the length of time that I hold down the button to shear, milk, or ride a mine cart (in creative) determines whether or not the action works without injuring the object. If I just tap, then I (for example) get wool and injure the sheep. If I press and hold for a fraction of a second, then I get wool without injuring the sheep. But if I press and hold for too long, then I get wool without injuring the sheep, followed by an immediate strike to the sheep that hurts it.
It still happens in MPCE 0.12.3, although there is some improvement.
It seems that the length of time that I hold down the button to shear, milk, or ride a mine cart (in creative) determines whether or not the action works without injuring the object. If I just tap, then I (for example) get wool and injure the sheep. If I press and hold for a fraction of a second, then I get wool without injuring the sheep. But if I press and hold for too long, then I get wool without injuring the sheep, followed by an immediate strike to the sheep that hurts it.