That means they already wrote 80 mins of music in, what, one and a half weeks?
I don't understand why they can't take a little more time for their albums.
Probably because they don't NEED to. Simple as that. What they are doing works.
Gotta agree with Bosk here. We can assume all day and night how much "better" the music could have been given a bit more time, but it's not like the music is particularly horrible in any respects, or at least to a majority of fans. What they do is pretty great, and the chemistry between Neal and Mike has always led to some great music.
Also, more often than not, Neal comes prepared with music he's worked on for months, and when he gets together with his bands, unless they offer up a ton of ideas, it's mostly his pieces that get tweaked by the band and re-arranged a bit, so it's not like they're writing from scratch every session. For all we know, most of the album was already written by Neal in the last few months (and actually, I recall Neal saying he had ideas several months ago for the next NMB album lined up, according to his Inner Circle Newsletter).
So no, I highly doubt they wrote an album's worth of music in less than 10 days, but more likely hammered out the tunes, tweaked them to include input and ideas from Mike, Randy, Bill and Eric, and finalized the arrangements. Between now and March, they'll probably discuss arrangements and ideas some more, then finalize the drum tracks during the tracking period, then spend the next couple months recording the rest of the instruments and vocals, which then will go through numerous edits and tweaks between the band members as mixes are sent back and forth between them via email/dropbox from Neal and Rich Mouser. The final mix probably won't be done until a month or so before release anyway, which they have all year for if they want it out before 2019.
You can tell I've watched WAAAAY too many Neal Morse/SB/TA/FC behind-the-scenes/making-of documentaries. It's a process, and yes, while Mike and Neal have written stuff in the studio before, they typically come prepared with the majority of music to be recorded. Demos for many of Neal's albums exist, as far back as the SB days, to prove that he does write before sessions begin. Dream Theater they are not.
-Marc.