Rotate... definately.
I have two blue vandoren cases which I've taken the charcoal out of. One keeps my bevy of Rico Select Jazz (yes, its RSJ, not RJS... I know, it doesn't sound right, but check the thread on SOTW... on to digressing...) 3M which were hand selected with certain criteria (balance from the factory, stock, left-right. Eveness at the heel, purity of the heart, etc...) through visual inspection out of a box of 10. I carefully broke in each reed over the course of about a week, while spending most of the practice time on either older reeds or one of the lesser quality 3Ms out of the box which wasn't broken in over a period of time.
In my second case, I keep 2 Gonzales 3.5s which were lightly worked with some sandpaper, and 2 Gonzales 3.75s which were more thoroughly worked. This is for my classical/pre-2-weeks-ago-concert-band setup (R. Caravan mpc). Since I got my Meyer 6M, I had been using some old worked over RSJ 3Ss, but had a few squeeks, but this wasn't molded to my Caravan (the others held the MPC back, on top of being set up for something with a tip opening of .012inches narrower). I picked out two candidates from the same RSJ 3M box (only box I have right now) and took them to the sand paper. Soak, test, sand, rinse, test, soak, sand, rinse, test, etc... One of them came out really nice, one of them... was just OK. Anyways, right now I have just "my 6M" reed and my "sit in a cup of water incase the gig reed breaks" reed (some may say "back-up", I wax poetic... poorly). I need to buy/build a new reed case and pick up another box of reeds for the new mpc.
FWIW, I rotated those 4 RSJ reeds for the Caravan from September through late May... The Gonzales are great reeds, but as they run a bit on the hard side, I'm going to need to pick up some 3.25s before I'd switch on the R.C. I have 2 designated as concert-ready, and two for practice, but rotate all four through practice until right before a performance. They've lasted a long time after some careful break in.
Just what I do...
**BRENT**
P.S. For as good as I am, this is WAAAAAY overkill. Just part of being a gear head, I guess, and a tweaker-at-heart.