The necessity and value of retweeting the same thing many times so more people will see it isn't lost on me. That's the way it works on twitter. If you tweet something only once, very few people will probably see it and many who wish they had seen it will miss it.
If you follow a couple thousand people (at the least) as I do, tweets are constantly racing along your timeline. So many tweets speed down the screen that you can't possibly look at all of them, much less click on every link in every tweet. You would need to do that all day every day, including at night, and even then you wouldn't have enough time.
Having said that, I should think any self-respecting writer would use twitter for more than that, and seek to win over persons like me who are looking for something beyond a plug for your book. You're a writer and twitter is for writing, right? Or are you so limited as a writer that you can't think of anything else to tweet? Isn't a real writer compelled to tweet something beyond a sales pitch if he's spending time on twitter anyway?
Is there nothing else in your life besides your book you would care to tell us about?
- Bake a nice pie?
- Meet a weirdo at Walmart?
- Yoga class?
- New shoes?
- Your favorite TV show?
- Something stupid a politician said?
- Current event in the news?
- Your sports team?
- The weather?
There is no end to the things you could tell us about in the space of a few seconds besides "Buy my book!" I can't be the only one contemptuous of such authors who have nothing to say but "Buy my book!" How can they be worthwhile authors?
I have much more respect for writers who announce new blog posts, or even just some "frivolous" tweets informing me what was purchased at Whole Foods. I mean, anything, just anything more than "Buy my book!" gets my respect and I think much more highly of those writers than others, and I'm much more inclined to read their posts, click their links, and even buy their books!