Fly-by-Wife,
Please tell us where the requirement to maintain an adequate lookout is not required in IMC. The rules of observing traffic and avoiding collisions apply in all flight conditions.
unless one pilot is an instructor and the other a sudent, then only one pilot can log the time. It doesn't matter which, as long as the time logged is appropriate for the ratings held. A non-IMC/IR rated pilot could not log any IMC time, for example.
Ever heard about a part of the law requiring more than one pilot?
Simulated instrument flight is one such example......it requires two pilots even in a C150. See JAR-FCL for definition of co-pilot.
A basic PPL can put on a hood and fly in simulated IMC provided that they have a safety pilot. They can log the flight time by sole reference to instruments as such.........to do otherwise would be to make a false logbook entry.
If their safety pilot is IR or IMC qualified and is the pilot in command they can even do so in IMC and in controlled airspace.
What they can not do is claim that time towards an IMC or JAR-IR rating.
Perhaps you need to differentiate between logging time and claiming experience when applying for a licence or rating.
Regards,
DFC