I've tested this method and still using it currently. I don't have the summoning level for the Terror bird, but I can still get about 10 kills per run while picking up charms other than gold. Instead of super attack I use a combat potion, mainly because you get a boost to both attack and strength for only one inventory space. The only main issue with this method is going through the portal room with the Shadow Spiders. My combat is around 104 so they are still aggressive and usually drain all of my prayer (Prayer level: 60). This means a decent loss of profit because a full prayer potion is pretty much required each run. I don't see any way of avoiding this initial loss of prayer points though. Sometimes prayer isn't even necessary if someone else has the aggression of the baby black dragons, or if you can trap them behind the green dragon you are killing.