Think I've got the the hang of it after the first 50 or so. Using a queen marking pen to mark a clearer centre point at the business end helped improve my aim, and you get a feeling for the pressure to apply
Yep, why make extra work for myself?! Especially as the only reason I haven't spun the uncapped stuff to put in feeders is to avoid the work involved. Will store the extracted supers wet, and if I run out of ekes (per Michael's reply) nadir the rest.
After extraction I'm left with supers of empty comb (wet extracted), and some supers of mainly unsealed stores which i haven't spun out. I'd like the bees to move as much of these stores as possible to my (14x12) brood boxes so i don't have to feed syrup. So, when returning the unsealed supers...