I have coded a python app in my spare time to auto-sync two subtitles streams (any langage) and maximize the time each dual-subtitle is displayed on screen. It just tries to merge two srt as smartly as possible. I'm interested for feedbacks and test cases, my mail in my profile.

But sometimes, doubling amount text on screen is just not processable at a glance, fleex seems to have very appealing solutions to that : picking one of the langage based on difficulty, arrow key to get back in time and slow down playrate. Cant' wait to play with it!