Rocket and Orange Salad

What is your view on frozen fish?  Living in land-locked Oxfordshire, our fresh fish supply is not brilliant.  Sometimes, you get good stuff from Hayman's fishmonger in the city's Covered market, but not always.  I long to live by the sea where you can get fish fresh from the harbourside, but until then, I certainly don't eschew frozen fish - some of it can be very good and cooks from frozen.  For example, Waitrose do fillets of Scottish mackerel, and they are superb - juicy, fresh-tasting, and crisply-grilled from frozen in 10 minutes.  We had some last night with a mustardy potato salad, and this lovely zingy green salad.  Get good, organic rocket with a bit of texture please, and a summer navel orange from South Africa.  Peel the orange with a sharp knife and then cut out the segments, over a bowl to save the juice.  Now, in a salad bowl, put the orange juice, salt and pepper, a tablespoon or so of chopped parsley and a tablespoon of rinsed nonpareilles capers.  Add a couple of tablespoons of good olive oil.  Toss in a couple of handfuls of washed, dried rocket and the orange segments.  Serve with the mackerel and spoon the orangey juices left in the bowl over the fish as it comes sizzling from the grill.