I've found it weird to say the least that usenix doesn't accept troff, but will take Word documents. 

The plan 9 troff pipeline is still quite complete. A few years back Russ Cox pointed out that new CPUs were so fast that running a statically-linked troff pipeline to process a paper was pretty much instantaneous. 

He was right and, for a few years, for tech papers, I just switched back to troff/tbl/pic/grap and friends. It was nice.