OMG just now I thought to do the Google search on "define renga" and it helps a little the understanding! Renga it turns out is a traditional Japanese poetry form, a collaboration between two of the individuals. In his public release announcement for this game, the author tells:
Keep in mind that what you type is much a part of the poem as the verse.This suggests that there is collaboration between the player and the parser.
The author of this game is also the author of More, which I like in the recently complete Shufflecomp. In his post comp release and reflections on More post, Jason asks people to download and give a try Renga In Four Parts. I was happy to do that. Unfortunately, I don't understand this game. I find it hard to "get" into.
I played a few times, using the "toggle script" option to save three of the poems. Game seems to make a frequent change of subject from the last verse and/or from the player's last word. I did not find that it sums to a story or vignette or tableau coherent. I tried to work with the game, for example typing in words in each part that correspond with the title of the part, but I still got this feeling of the leaping around subjects. There are interesting pieces (a he, a she, a tree, to name three) but I think more constraints are needed to tie them into a meaning whole.