I've heard the rumors about HBK/Rock, too. Something along the lines of Vince wanting HBK to work some with Rock, even just house shows and such, because they had big plans for him and wanted him to work with the top guys to learn but HBK refused because Rock was, at the time, "below his level."
But enough of that, I saw something else interesting in this thread - HBK -vs- Eddie. Did anyone know that match was actually in the works before Eddie died? Everyone likes to talk like Eddie was supposed to regain the title the night he died but, according to an interview I listed to with the SmackDown writers at the time, that was never the case. According to Bauer and Greenfield, Eddie was supposed to complete his heel turn on Batista before the end of the year and, in January, start setting up his Mania match - with HBK. The basic outline they talked about was that Eddie was supposed to be jealous of HBK's fan support and such after he'd been such a huge prick. HBK was a drug addict and asshole backstage but, "found religion" and everyone forgave him for everything in the past while Eddie was also a former drug addict and problem maker backstage (for storyline purposes) but after he'd cleaned himself up nobody was supporting him like they did HBK and he wants revenge.
I typed up a more in-depth explanation of this feud a couple years ago when I first heard the tale, if I can find it on the old forum I'll repost it here.
It might sound like a weak story but with two of the greatest characters and workers in the business, you know damn well HBK and Eddie could've made this one of the biggest feuds and best matches of the year.