In RoTJ, it seems that Luke leads a plan to rescue Han from Jabba the Hut. However, the details aren't clear. Two rescue attempts are made, but they are foiled, and an overall plan doesn't seem apparent.
At some point, Lando infiltrated the guards, and later we see C-3PO and R2D2 presented as gifts, smuggling in the lightsaber. Then Leia shows up in disguise with Chewbacca in tow, and seems to rescue Han, but is thwarted. Then Luke shows up and tries to use Jedi powers on Jabba, but he is thwarted, too.
So what was the master plan? Just get everyone in there and wing it? Was Leia supposed to lead the rescue herself? If Luke thought he could exercise Jedi powers over Jabba, why make things riskier with bringing everyone else into the palace?