Ellen Pompeo and Patrick Dempsey by Frank OckenfelsABC Ellen Pompeo and Patrick Dempsey by Frank OckenfelsABC

You won't believe this, but I once again found myself in a hospital while in Los Angeles covering the TCA Press Tour. But unlike the Root Canal Crisis of 2005, this year's medical intervention didn't involve any pain, just some mild heart palpitations, high blood pressure and sweaty palms. And the doctors attending to me bore the names McDreamy, Meredith, Izzie and Addison. If you haven't figured out where I'm going with this yet - and if the headline hadn't already given it away - I pity you. I, along with 60 other TV critics and reporters, was admitted to Grey's fictional Seattle Grace Hospital on July 20 for an emergency tour of the set and a brief consultation with the cast. I was sprung after only an hour, but I learned quite a lot during my Anatomy lesson. For instance:

1. Shonda Rhimes is loosening up on her spoiler policy.
Not only did the onetime Information Nazi announce that "the fabulous Miss Diahann Carroll" would be one of the new season's first guest stars, she also dropped this mini-bombshell about the premiere: "It basically takes place hours after the last [finale] ended. It's not like we're going to do a big leap forward in time, and everybody's fine and nothing's wrong with anyone. I don't do that." And there's more! When I asked her to confirm my report from earlier this summer that Eric Dane's McSteamy was headed back to Grey's as a regular, she offered this telling tease: "People sent a lot of e-mails and letters for a guy who appeared in one episode."

2. Patrick Dempsey is growing impatient.
Think you're ready for McDreamy to finally choose between Meredith and Addison? Try being his portrayer. "I was at wit's end towards the last year," he concedes. "I think we've got to make a decision, and I think that's what they're going to do." However, he stopped short of constructing a white picket fence for Derek and Meredith. "I don't know if he necessarily ends up with her," he says, "but I think they should explore what they began at the end of last season... as opposed to him following her around and looking at her longingly, going, 'What are you doing?' I think it castrates him too much, and I think he needs to get his masculinity back." And it's not just me he's voicing his opinion to. The ex-Loverboy says he's in constant communication with boss Rhimes about the direction of Derek. "It's a continuing dialogue after each episode," he says. "I think it's important [that] they have a through-line for all the characters, so I have to go in and say, 'What is your mission for this season? And how do I help you with that, knowing what I know [about] the character and what I feel for the character?' I think it's going to be an interesting year for the show to see how we develop that dialogue."

3. Katherine Heigl wants to stop playing doctor.
It's the question on the minds of all Grey's fans: How the heck can Izzie wear scrubs again after the numerous ethical violations she committed in the season finale? According to Heigl, she can't. "I don't think [becoming a doctor] is something [my character] should pursue anymore," she admits. "I think she's pretty much played her card. And I think if she wants to continue to be a doctor, she needs to find another way of doing that. I think she really has to find a new heart to do that. She can't be Izzie and do that. She has to be somebody else." Heigl is quick to point out, however, that Izzie may be many things, but a killer is not one of them. "She did save [Denny's] life," she declares. "He just rejected the heart. She didn't kill him, but she nearly did." Personally, I think that's a pretty big distinction.

4. Ellen Pompeo has no opinion...
... about the impending showdown between Grey's and CSI on Thursday night. I know this because, as different packs of reporters rotated over to her corner of the set, she was asked the question, like, 10 times. And each time, her answers became shorter and terser. "It's fantastic," she semi-snapped at one point, adding, "I don't think about it unless I'm asked." (And did I mention that she was asked? Over and over and over....) Truth be told, Pompeo didn't have much of an opinion about anything, often giving one-word answers to questions, or simply not answering them at all. What was her favorite scene on the show so far? "I don't know that I could single out one." Has she ever watched CSI? "No, I've always worked." How long can the Meredith/Derek/Addison triangle play out? "You'll have to ask Shonda Rhimes." How does she feel about Dempsey saying that the ongoing triangle is castrating Derek? "I don't agree, I don't disagree. I just don't have an opinion." What did she do on her hiatus? "I did press in Europe for the show, and it was great." I eventually had to walk away out of sheer discomfort. I'm sure Pompeo is a lovely person, but after being interrogated by 30 reporters in as many minutes, I don't think there's anything anybody could have put in her IV drip to perk her up.

5. Kate Walsh loves poison...
... ivy! Well, she loved the episode in which Addison discovered the itchy skin rash on her vajayjay, anyway - this despite the fact that shooting those scenes was no day at the beach. "It was long," she recalls. "And all the writhing around... I actually got out of [the stirrups] and there was definitely a little lower back pain. [But] I thought it was really funny. I've always been game for a good joke." She admitted it was probably that episode that marked a turning point in viewers' love/hate relationship with her. "Audiences are more sympathetic to [Addison], and people are much more verbal about it now. They're like, 'I didn't like you when you first came on, [but] now we love you, we're rooting for you!' It's great." Gotta remember that ploy if my approval ratings ever nose-dive. (Like that would ever happen.)

6. Chandra Wilson's into foursomes.
Remember hearing about (and possibly seeing) the now-legendary Grey's parody at last May's upfronts? The one that lampooned George's famous dream in which he climbed into a shower with Meredith, Cristina and Izzie, only this time it was Bailey getting all sudsy with the Chief, Derek and Burke? Well, Wilson had as much fun making the clip as we had watching it. "It was goofy - and that was the intention," she says. "We said, 'Look, this has got to be funny. It's meant to be goofy. You can't take it too seriously.' So it was cute just making fun of the girls." Wilson wasn't surprised that the vignette made it onto the Web, but she was a little dumbfounded when friends began e-mailing her links to it. "They were like, 'Have you seen this?' I'm like, ' Hello! I'm in the thing.'"

To find out what else I learned on the Grey's set - including Dempsey's surprising reaction to the shower parody and Heigl's thoughts on when Izzy's daughter might show up - check out next Wednesday's post-press tour Ask Ausiello extravaganza!