Place lamb in a shallow non-metal bowl. Combine oil, lemon rind and juice, vinegar and italian herbs in a bowl and season to taste. Pour over lamb and turn to coat. Cover and chill for 1 hour.
Heat a barbecue plate on medium-high. Cook lamb on barbecue, frequently basting with marinade, 4 minutes each side for medium, or to desired done-ness. Transfer to a platter, cover, and let rest 5 minutes before slicing.
For Feta and Parsley Pesto, place parsley, capers, oil, garlic, and lemon juice in a food processor and pulse until roughly chopped. Remove, stir through feta and season to taste.