That's only a concern if you consider yourself an HN'er first and entrepreneur second. If your goal in submitting is to provide high-quality material for HN, then you wouldn't use meatpuppetry. If, on the other hand, your goal is to drive traffic and you don't care about HN, then you use whatever means you can. It's the same for people who spam craigslist trying to get users. They're polluting craigslist and lowering it's quality, but they care about traffic, not craigslist. If it's acceptable to do that (and most startups do), then it's acceptable to game HN.