I'm reinforcing what others have said. I recently took my SA on a three day trip to Fort Flagler. I packed my clothes in a Tri-Star/Wester Flyer PCBP and it fit well in the SA. Part of the reason I bought the TS/WF PCBP is because the vertical Freudian slip fit in it. I wanted to be able to take my writing supplies in a backpack to a different part of the campground. The Freudian slip in the PCBP worked well for this.
@Ilkyway. yes, when I write about the Synapse in this thread I am referring to my Synapse 25, since that is the bag I know you use. In practice, Although I use both sizes of Synapse, I'm more inclined to use and travel with my Synapse 19. I almost always carry a laptop with my Synapse Backpack, although it might be a 13" MacBook Air. Consequently, this is always against my back inside a cache or a cache with rails (in the case of my Synapse 25). I know you've read @Tachiyaku's post about how using the cache with rails improved his Synapse 25 carrying experience. I haven't tried to pack the S25 for a purely clothes carrying trip without the laptop, but I'd probably choose my packing cube sizing to try to conform to "flat-packing" principles following the curves of the bag to keep it from "egging". Not a complete answer, I know, because I simply haven't tried to do this yet with the S25.
Originally Posted by Ilkyway
bunchgras: you switched the light bold on. Now I understand what you and moriond mean with the freudin Slip and the PCBP. I thought: why would I want to pack it in the PCBP when it can sit in front of it or behind but you mean at the destination going out without the SA and using the PCBP with the Freudian Slip. Don't know why I did not get this before. Maybe the thought of leaving behind my SA (or my S25 for that matter) just is not thinkable for now. I think this will change when the hot season arrives.
Thanks so much for explaining, answering and bringing me new ideas.