you can use the keg to make the bottling easier!
purge your keg with co2, I like to fill it to the brim with star san and push it all out with co2.
get all set up to rack to the 'bottling bucket', your priming sugar boiled and cooled, any extra yeast ready to go, etc.
then pop the top on the keg and add the priming sugar and any extra yeast you wish to use.
rack the beer on top and seal it up. purge the headspace one more time and then shake it up. you can actually be pretty rough at this point because it's in a near 0 o2 environment. everything will get nicely distributed.
now attach your bottling wand to the end of the cobra tap like this
and push the beer into bottles with co2. it's a little change in procedure that makes the whole process much easier.
the other option is to keg with the priming sugar and let it naturally carb up then ice it down for service.