I am a postdoc in computer science. At the end of my first year I have submitted a paper to a reputable conference, co-authored by me, a PhD student and my adviser. It was recently rejected. Reason: it was a rushed submission at the insistence of my adviser, the project simply needed more time. Our submission was published as technical report on which he is a co-author.
At the beginning of 2nd year we have agreed that I will continue my work on this project and will turn it into a strong submission. Now, midway this project he gives me an "offer I cannot refuse": either I produce 2 papers or he fires me and expects me to finish the paper on my own.
To be short, he believes I cost him too much and is desperate to do some salami slicing. He wants to cut our planned strong paper into 2 weak halves. This could work, but could also lead to another round of rejects and wasted effort. In addition, the pace at which he expects me to work is unsustainable. Poor judgement and abuse, if you ask me. In addition, I quite disagree with his style of editing which emphasizes overstatements and "selling" over accurate technical contributions.
I expect to be fired any day now. His participation in this work, at least from my side, was financing me, supervising and editing the draft. By supervising I mean weekly meetings, listening, asking questions, mostly agreeing.
The research design and implementation is entirely mine. The original idea was proposed by some external collaborators who didn't wish to participate in this research.
My plan at this point is to remove the work of the PhD student (because it doesn't fit well the rest of the paper), add all the work I have done so far, re-write the whole paper and publish as sole author. According to ACM policy he won't have any substantial contributions left. As you can see from above, I question the quality of his contributions at all levels and am quite confident I can finish this work on my own.
He insists he still qualifies for co-authorship because he financed most of the research. However he is unwilling to finance me until the submission and expects me to finish the work on my own.
Question: What repercussions do I risk if I exclude him from co-authors?
I don't expect to get any good recommendation letters from him anyway, so this is not an issue.