Laurie Goulding made enough offerings to the Chaos Gods in order to become a Black Library editor. He pleased the dark gods enough to become chief fuck-up officer for the Horus Heresy novels. He is not beloved by the community; and though he's fucked up a lot, he's not as hated as some, mostly because his name wasn't front and center on every thing he touched and no one knew who the fuck he was.
During his tenure as King of the Nerds, he saw some of the worst side of the fandom. Which is ironic, because he's a good example of a bad fan. He's publicly whinged about fans demanding that Games Workshop pay the emailer for compensation, because something in a Black Library book was similar to their made-up chapter or something. Laurie's lack of experience in publishing betrays him here; that's part of the job, and not really worth bitching about. Laurie has written for Black Library, but it's forgettable stuff. Goulding also took *cough* inspiration from various sources, but because he's not terribly well-read, got called out pretty quickly. Accusations of plagiarism aside, he's not known for his originality.
He is known for being sarcastic, abrasive, and egotistical towards fans. He even had his own forum. This is after he tried going on dakkadakka and Warseer and was called on his bullshit. And of course, he's one to hold a grudge.
The Ascended Fanboy
Once, Laurie Goulding was one of the most ardent of all 30k fanboys, back in the day when 30k was not even the ghost of a thing and was only in a forgotten card game by Sabretooth. His fandom was such that he created his own 30k fanwebsite called 'The Great Crusade', which he hosted. He lucked into a job at Black Library as a continuity editor, despite failing the editorial tests during the interview. He got the job because he was able to point out several major goofs, including both Fulgrim and Magnus commanding the 28th Expeditionary Fleet at the same time.
TL:DR - The classic nerd syndrome. As soon as he got a whiff of power and influence, he used that to bully other fans.
Unfortunately, Goulding tends to embody and reaffirm a lot of the problems that people have with Games Workshop. While he does honestly try to have contact with fans, he doesn't seem to listen to what they have to say - instead preferring to say that the fans are foolish for interpreting a novel a certain way and say how good the novels have been and how they're getting even better. This is a problem, because it suggests that instead of seeing why fans are interpreting things incorrectly and looking to correct it in future novels, he just openly mocks people and keeps assuming he's doing it right (a true Daemon Prince of GW, indeed).
He has said that he does make changes when fans correctly guess twists. This also suggests that having a twist was so important to him that he would rather change the plot so it's harder to guess. This last minute change has fucked up more than one book, and Laurie has admitted that he's done it for petty reasons (possibly because he thinks that most 40k lore isn't very predictable and is mad when he's wrong).
The last big problem some have had with Goulding (aside from people's normal complaints) is his take on canon. Much like many people's complaints with an infamous Games Workshop employee, he has a bit of a these are my ideas and this is how it is take with the canon. While other authors and employees may allow wiggle room for your own ideas and theories to unfold, Laurie Goulding tends to have an idea in mind and for that idea to be the only one. This is fine with fan works who are interpreting cryptic or completely untold lore, but for someone official to say that your idea for your beloved chapter is completely wrong (probably followed by "and you should feel bad for it" if it's coming from Goulding), then it's a bit disheartening.
Goulding is also adamant that Blood Ravens are not Thousand Sons (or any other loyalist Chaos chapter), and that only current edition codices are canon (RIP Malice). This has since been contracdicted by other GW staffers, so who the fuck knows.
End in Disgrace
Laurie was pushed out of his position. Too dumb to quit and too useless to be re-assigned, they essential made his role untenable by expecting him to do a normal workload rather than fucking around on Skype with his friends.
Luckily, he has since fucked off to the States to piss off fans of League of Legends instead. There was much rejoicing from the 40K community. GW has since hired people who know what they're doing.
He is not Sandy Mitchell, who has more talent in his foreskin than Laurie has in his entire body.