Full length articles or multiple letters to publish in Journal? Prior to submitting a Journal article, I had a conversation with my supervisor about whether it was suitable for a letter (max 4 pages) or a more detailed article (max 12 pages). My position was that the core contribution (a new method) could be concisely and completely be described in less than 4 pages, and should therefore be a letter. The complication was that some progress had been made on the application of the method to a particular problem.

I therefore wanted to publish the first letter straight away, and later publish a second letter later dealing with the application. My supervisor didn't like this idea. He said it was "playing the game" to increase one's own H-index, and it was more suited to a single article. I subsequently took his advice to submit a full length article. However, now (with the article submitted over 3 months ago, and still under editorial review) he has changed his mind and says it's "up to me" as to whether I would like to withdraw it and resubmit as 2 letters...

So my question is whether there is any disadvantage to publishing research as a series of short (more concise/readable, and faster reviewed) letters in the same Journal?

(In this journal the letters are also mandated as open access, which is an option rarely used for the full length articles, and may improve findability)
My advice would be to go through with the submission as is. If you were to withdraw the manuscript you would then have to write the two new papers and go through review for each of them. These steps take a lot of time and effort, both of which you could spend on original research (e.g. use this new method to solve various other problems).

The only case where the resubmittal might be interesting is if your results are so novel and significant that you are almost sure you can publish them in a high-profile journal (more prestigious than the current one). Then again, if they had this kind of potential I guess your advisor would have spotted it...

Generally speaking, having two papers (one of them as a letter in a prestigious journal) is of course more gratifying than one long publication and looks better on the CV. There are however two points to consider:


The results need to be important enough to warrant publication as a letter. In particular, the (uncertain) benefit of having it published must compensate the investment in time and effort (see above).
The "long paper" should contain enough new material to stand on its own. "Salami slicing", also known as the search for the "minimum publishable unit", is frowned upon. Although this behavior is not apparent from the publication list, it can be detected by careful examination (e.g. by the candidate's referee on a hiring committee).


See also this thread for more details.