I second that.
I remove the push rod from rear brake making sure the piston inside the master cylinder retracks all the way out.
Remove the fluid resorvar from the hose running down to mastercylinder.
Fill seringe (big one) with fluid and attach a peice of clear tube that fitts snugly into the hose that you just disconected the resorvar from and zip tie it to improve seal.
Push pistins all the way inside caliper.
Fit clear pipe to caliper end and run it into a container to catch fluid.
Open bleed nipple.
Now begin to push fluid using the seringe it will be ferm to push but should move. If fluid wont flow recheak mastercylinder pistin is not sticking.
Once all the air bubbles have stoped coming, close bleed nipple and cheak brake for presure (pumping push rod/lever for 20 pumps with something wedged inbetwn the pistons in the caliper until ferm).
When you are happy remove the hose from the mastercylinder end and reinstall resorvar, cheak fluid level.
Reasemble and go ride.
Once you have mastered this method it is quite literaly a 5 min job.
I also like the ideas of prefilling caliper and pushing the fluid back out to prime.
Hope this helps someone