Except that your link answers the question of whether the CFI may log an approach, not pilotinsky's question about whether the instrument student may log PIC in actual. So answering the initial question instead of the most recent onw can be a bit confusing

pilotinsly, don't deduct that time. It's is logable as PIC by your student because your student, a private pilot, is the sole manipulator of an =aircraft= he is rated for, which is all that is required for logging PIC time.

The FAA Chief Counsel has been saying so for at least 29 years, with the latest confirmation coming earlier this month:

http://www.faa.gov/about/office_org/...9/Haralson.pdf