I don't think Tracklayer's City a viable method, unfortunately - I think under the best possible circumstances (minimal deck of 12 standard and 1 rare cards) you have about a 1/9 chance of drawing Imports and Exportsm so you'll get about 1 document every 9 actions. However, looking at the <a href="/wiki/Legal_Grinding_(Guide)" title="Legal Grinding (Guide)">Legal Grinding (Guide)</a>, I realise this page really needs updating to account for barristering at Evenlode - if you get dubious testimony from <a href="/wiki/Enter_the_house_(White)" title="Enter the house (White)">Enter the house (White)</a>, that's 3.2 actions getting enough testimony for a case plus 6 for the case itself to get 2 documents, thus 11.25 OaW/action.
I'm not sure that makes this a good notability grind, although it has been a while since I did paramount so I'm a bit out of touch there.