It would be an easy matter, technically, to log all calls made by a lawyer to a client within the company and all intra-company calls from clients to the lawyer. This recording would disregard all content, storing and aggregating only the people at either end and the duration of the calls. Since many lawyers spend much of their day on the phone, this unobtrusive tracking mechanism could substitute for some of the information laboriously (and often erroneously) secured from recording time (See my post of July 12, 2010: sloppiness in time tracking by outside counsel.).
I have already written about construction of a client-contact network (See my post of May 11, 2010: network metapost). If, then, in addition to modest tracking of phone traffic, client meetings were the subject of time recording, I believe there would be a quite full picture – and an accurate contemporaneous picture at that – of what an in-house lawyer does. Stated differently, three different techniques should substitute quite well for the onerous task of retroactive remembering.