To close the loop on this thread.
I ended up not having to disconnect the hydraulic hoses to pack the bike. I used a box a LBS gave me (a humongous Scott box i had to trim in length to something more manageable). In the position pictured, the bars wouldn't fit in my evoc bag, so next time i use that bag i will either have to get creative to get the bars at a 90 degree angle, or disconnect the hoses.
To be fair, i ended up re-bleeding the brakes anyway because i'm in the mountains for the summer and wanted all the stopping power i could get, and if you travel with (all) your tools, it's not too bad to trim, olive, barb, re-bleed. But obviously, better if it can be avoided. Especially if you only travel for a few days.
Also, a point to note: if you have enough random stuff to stuff into a cardboard box, and are ready to play duct tape games to fix things and what not, you end up with a bike that's better protected than in these soft ("semi rigid" = not rigid = soft) bags. So... given the cost of these bags, if you live close to a LBS with a constant supply of boxes, if you dont have to take public transport with your box, if the taxi is big enough for the box (a lot of ifs), a cardboard box will likely offer better protection, and you can recycle the box when you're done, instead of having to store an awkward shaped bag.