Sorry but you are totally incorrect
and checking or unchecking the preference does nothing for the past - it simply does what it says - it either copies or does not copy imported items to the iPhoto library - not copying them is strongly discouraged and is likely to be yoru problem -- with the latest version of iPhoto and Aperature you can reconnect the links and in most cases iPhoto Library Manager - http://www.fatcatsoftware.com/iplm/ - can do it
back to your incorrect post - all photos have to be on your hard drive, maybe the internal hard drive or maybe on an external hard drive, but they have to be on a hard drive to be accessable -- and photos on a hard drive take ZERO RAM - they have no effect of any sort on RAM use
as to qualifications - you may note that TD is extremely well qualified as shown by the amazing number of people who he has helped - I note that you never have helped a single person - so qualifications are easily determined
You have made poor decisions and have a mess on your hands as a result of your poor decisions - snide attacks on people trying to assist you are very much out of line
LN