It's all a matter of balance. I've known (and still know) writers, who will talk rather like literary fishermen over several pints of beer of their magnus opus, the one great story that will make their fortune and fame. Over the years, I've become far too intimate with some of these stories, most of which had yet to take form in a single inked word. A blog can become rather like this. It can be a place where you indulge in a little trumpet blowing or even innocently spend all your time declaiming your plans.
There's a lot to be said for putting you intention out into the world. If it's done with serious thought and for-planning then blogging about a project is as much for yourself as it is for your audience. You can use a blog to drawn your line in the sand and say I will do this - ever aware that if your blog is becoming in the least bit popular you'll look a right idiot if you don't do it.
But we all have lives beyond blogging. I've been quiet the last couple of days as I wrestle with a tricky family matter where the old guard have asked me -as one of the young 'uns (they're all in their eighties) - to sort out a difficult family matter. I've had re-allocate my already precious time to cope with this new demand.
In particular I had to choose between returning to this blog and finishing a proposal for a new (and I think) very exciting project. I chose the to finish the proposal.
It's not a straightforward choice. If a blog is inactive for a few days, especially early on, it is likely to dropped by readers, who assume it has gone the way of other ether musings and faded into disuse. But then if I don't put the work first I'm blogging about blogging - in which case this ceases to be a professional blog and becomes more of a personal journal.
A professional blog is for life not just for Christmas, but it must always be run in parallel, and as a support, to your profession.