Quite possible. One of the reasons I do Stratum or Stratum Proxy is to lower/eliminate stales as the server ' decides ' who gets a block of date to work on and not just keep dropping the same work to whatever asks for it. That is the theory at lest. In reality, if you are say hashing at ( the following is just example numbers blown out of proportion to drive home a point ) say... 85kHash/sec scrypt ( as oposed to the much faster Sha2586d ) and another miner gets the same block to work on with their 15 mining rigs doing a total hash rate of 500kHash/sec there is a big chance due to the multiple miners splitting up the work load that one of them will submit prior to you for the same work load.
The reality is that Stratum does lower stales over all the pool, not the individuals. In order to lower at an individual's side stale submission, either increase the number of units mining ( CPU, GPU, FPGA, ASIC, PI mining hybrid cluster, whatever it takes ) to increase the total hash power on your side of a stratum proxy so as to ' start hashing ' higher up within the block in order to find the shares.
For those that still believe CPU mining can't be profitable, they are forgetting SHEAR CPU MASS POWER of say.... The Cray III and how many individual CPUs were in one. Also the following link....
http://blog.afkham.org/2013/01/raspberry-pi-control-center.htmland for those that won't click a link unless it involves LEGO
http://www.zdnet.com/raspberry-pi-meets-lego-in-supercomputer-like-cluster-photos-7000004209/It won't stop the individual hash rate at such abysmal levels, it will make a force not to be messed with. Where I live, I have friends at the local recycle station that will ( on really rare occasions ) let me take home what's left of ' dead ' computers. I already have a few ' spare ' routers, just not enough solar/wind power to get them all going ( and really stressing out the inverter as is
)
So, from my little rant to a possible solution for you, get your paws on a second ANYTHING that can do wired ethernet and have it ' talk ' to a stratum proxy on your first one and see if the stales start dropping. When I say anything, I do mean anything as in a newer phone, TI Beagle Board, MP4 player that has been hacked to do CPU-ARM mining. Anything to start splitting up the work load a little. This is mining and as we all should know by now, every hash counts.
Good luck.