It can translate using google translate, but as mentioned in this thread before, this is just for a starting point.
After that you must polish the translation as best as you can.
I appreciate your well-intended efforts, but I am afraid I do not agree with your opinion.
Using a machine translation as starting point SEEMS a good idea, but it is NOT. On the contrary. It is a beginners trap.
Especially if the source is an English subtitle for an English spoken movie or tv show episode.
Let me explain you why.
First of all, and I think we already agree about this, translation will be inferior. Machine translations lack interpretation of context and feeling. Since the sentences will seem to be 'okay', it is very likely that a human check will oversee these mistakes. But for now, let's assume translation is perfect.
Next, you must realize that subtitling is not the same as translating. Subtitling involves much more than just translating. Even if the translation is perfect (which I doubt already), crucial aspects will be lacking. For example, English subtitles for English spoken movies are typically 100% verbatim, including al the "you know", "I mean", "hm-mm", "wow", "yeah", and repetitions and stammerings like "I-I didn't... didn't know" or "no, no, no, no, no". Typically, gaps are 1 or even 0 ms. Line breaks are considered only by mathematical line length instead of word groups. Durations are typically very short. CPS-ratio is not considered at all (which is impossible anyway, if it must be verbatim). Synchronisation is usually only so-so. Etc. etc. etc. All this is not *BAD* for English subtitles, it is how they are made and how they should be made. But for other (translated) languages it *IS* bad. After all, for understanding, the viewer relies totally on the subtitles. On top of that, note that English is a relatively 'short' language. For example Dutch, German. Latin and Scandinavian languages will need approximately 20-30% more text (number of characters). That means that lines will be longer (too long) and CPS-ratio will be higher (too high).
Fixing all this will take ages
So, using a machine translated subtitle as starting point will not only involve fixing up all the wrong or weird translations and sentence constructions, checking them one by one. On top of that, you will have to spot and delete all the unnecessary texts, once again, one by one. You will have to check and fix every line, one by one, for line length, CPS-ratio, line breaks, gaps, sync and so on. Compress, rewrite, merge, re-break en resync them. One by one.
You may now understand that creating a good subtitle from a machine translation will take more time than creating it from scratch. Trust me, I have tried And still, there is a good chance you will oversee wrong translations and similar mistakes. Basically, you are busy longer, with still a likely lesser result.
Reality: people will not do all that fixing, or no fixing at all
Knowing this, you can also imagine that a lot of people will not go through all this hassle and just delete the obvious "hm-mm", "yeah" and "wow", and obvious twisted sentence constructions. They will not bother with any technical aspects (if they are aware of the necessity of this in the first place). Next they are thinking they just created something decent enough. But they didn't. They didn't FIX the machine translation, they just CAMOUFLAGED it. With the evolution of machine translations, this tendency is going on for a while already in basically every language section.
Also, in reality, many people will just upload the raw untouched machine translation.
Machine translations will push away good human subtitlers
And here is the next point, not to be neglected.
A machine translation takes one minute. Fixing it up a bit will take 15-30 minutes. So someone is able to upload 'something' in no-time. This inferior subtitle will always be the first one.The first subtitle will get far most of the downloads.
A human translation takes way more time, let's say 7 hours for an average tv show episode, 15 hours for a movie. Would you spend all these hours to make something, when 95% of the downloads are already taken by users who downloaded the 'fixed' machine translation? I wouldn't.
The actual result?
So basically, the site will be flooded by raw or 'camouflaged' machine translations, which will only disappoint and irritate the downloaders, frustrate the real human subtitlers and cause unnecessary extra work for admins, who try to maintain at least a bit of quality and protect their users.
So, resuming, in my humble opinion:
providing machine translations is not a service, but a hell.
I am sorry this may sound a bit harsh, but I cannot make it nicer.
Thank you for understanding.