From the begining of November to now (end of December) I have done nothing in terms of seo or blog posts. I moved house and have a running battle with an internet provider and have had no internet whatsoever. - Before the move one of my blogs was receiving roughly 100-200 uniques a day. - Over the period of 'no internet' I was able to check my stats via a local internet cafe and found I averaged 300-350 uniques a day. - This week I have been online (temporary still) and the uniques are dropping to 100-200 uniques a day again. ????!!!!!! This means that leaving the blog alone makes better stats.... Explain that then!
though I'm a newbie about seo, I think the most important thing is that you can bring something interest and new for visitors.
Working on SEO is a daily must do. Now you may not reap the rewards from it until a month or months later down the road but doing nothing will eventually lead to "no" or less visitors. There are so many variables when it comes to the amount of daily traffic. For your case for instance, it could have been that one of your posts or blog got on the first page of google for the month you weren't on it or someone could have bookmarked or tweeted some of your posts, so this lead to a flood of traffic for a month, etc.... Working on SEO and creating more valuable content daily will always be better and produce better results than not doing anything at all or doing less.