the adjoining farm next to our backgarden had sheep that was obsessed with getting into my backgarden - no idea why. they would jump over the 5ft wall with barb on the top.
When we complained he move the sheep to another field, they escaped that field and entered our back garden through a totaly different way - through our front garden. eating loads of our plants - I can understand the pain Clarkson went through (made up or not)
Nonetheless, sheep farming can be incredibly difficult, and sheep love to assert just enough independence to be annoying.