weaver,    in addition to what stringer said.....
2"  6G is all about speed, agility and a limber wrist (contortionist ... see prerequisite job skills). Fortunately (benefit of the sch 80) , there's enough mass/heat sink to get a full revolution (pass) around the pipe unless you are trying to weave, which by the way you should be running tight stringers in the 6G position. Still, do not let the pipe get hot on you. Let it cool down between passes, let a fan gently blow on it like the cooling fan at the back of the machine. On small bore, I like to "choke up on the rod"...or only use 2/3rds or 1/2 of the rod. Place rod in stinger approximately 1/2 way, then bend rod (the dead end) say 60 degrees, spin dead end 1 revolution minimum, wiggle it if necessary to clean off flux and provide good electrical contact to rod and stinger, finish bending dead end so it doesn't arc out on anything, do a mock/dry run to make sure you will maintain the proper angle for the entire length of bead ie. 1/2 way or 180 degrees...right??
It will be all about ablity to feed for melt off , rotate the wrist and contort upper body for angle of the dangle (proper leading angle of electrode) and maintaining line of sight on your puddle and where your weld is being laid down...There it is , piece of cake OK?? Did that help or are you thoroughly confused??? I think I am!
I think the most important part is the dry run so you know it will all come together B4 hand.

hope this helps

ps. on the up hill down hill, if you were refering to stacking the beads, on groove welds, always start at the bottom and progress uphill, sometimes on like overhead fillets, you can get away with stacking the beads from top to bottom, but I'm still not in favor of it. Yes often times they will look better, but thats because of improper bead sequencing, lack of planning (can't weld!!) and usually provides the UT technician, a chance to hone slag entrapment evaluation skills.