The fresher is better is true, however they will also eat frozen. the reason freasher is better is that the bloody pieces leave a nice scent trail. To answer your other question I would have to see the place, so I will meet you sat am and decipher it for you.
Seriously though if you check it out at low tide and see where the structure is, then know which way the current goes both incoming, and outgoing. You will be able to make some good choices. For example I have one place that is only good 3 hrs before high tide untill high tide, because of the way the current runs. Try to fish 1 whole tide at a new spot to see how and what happens.