I’m the kind of guy who’s always been of the mindset that traditional publishing is the way to go. Don’t get me wrong, I’ve had opportunities to speak with several indie authors and I love that they’re earning a living (far more of a living than I am with my day job) doing something they love. If I were any other kind of person I’d be jealous and rushing to join their ranks. Thankfully, patience is my middle name.
I’ve written and “trunked” three novels over the past four years for various reasons. I’ve had some short stories published, but nothing professional (i.e., no payment for the publishing). I’m currently working on (what I plan and hope to be) a series of novels I believe will not find themselves in the trunk. (In other words, I feel like I’m on the brink of some kind of success).
With this series, and more importantly the first book, I’m on the fence about whether to pursue self-publishing. For reasons stated here and here, I feel I want to continue with my die-hard pursuit of a traditional publishing contract. However, given all the buzz from the indie world (and some buzz from folks I’ve spoken with in the traditional world) I fully understand the need for an author to have an ability to promote and market his or her work, despite publishing options. With that in mind, I’ve been developing a website and working toward building an email list specifically to help with this promotion and marketing.
I realize this seems more a self-publishing tradition, but I assume (perhaps wrongly) that it wouldn’t hurt a traditionally published author to have a bit of a following. To help generate that following, I intend to offer short stories as a lead magnet to entice people to join my mailing list, etc. I’m also toying with the notion of self-publishing several other short stories and novellas to continue generating interest until (not if – fingers crossed) the first book is published.
Here's my question: given all the talk we’ve had about how bad self-publishing gives you baggage (and realizing that I would treat these short stories as professionally as I would a novel) would self-publishing shorts in this way be detrimental to a future traditionally published career? (i.e., I’m concerned about all the talk we have about sales figures from a previously self-published author with a second book being the “baggage” agents and publishers won’t want to touch.) I want to be proactive, but I’m also afraid (woodland creature)
My instinct tells me to be cautious, but it also says that shorts are a different animal than novels so I might be okay.
You're just not phrasing this correctly. Here's what you mean to say: I'm building my mailing list by publishing work that will appeal to people who will want to read my novel.
Once you phrase this correctly, you understand this is a very good thing, and huzzah to you for taking the promotion bull by the horns and giving him a waltz around the dance floor.
Far from being a detriment, this is something that would make me sit up and take notice in a query. You don't need platform to sell a novel, but if you include "I have a robust mailing list of 500+ readers" in your bio, well, yes, that makes my fin wriggle.
And if you need an example of a guy who's doing this, you need look no further than Jeff Somers. Follow his Twitter feed to see how he promotes his self-pubbed stories, and builds his mailing list. Jeff is a lot of things (likely drunk, likely pantsless, likely to be eaten by zombie cats after the apocalypse) but not proactive isn't one of them. He calls himself lazy; I roar with laughter when he does. Watch what he does, not what he says.

