That said, the new compose offers some other, more immediate UX benefits. For one, it makes multitasking easier, leaving you free to search through your inbox for some scrap of information you might need to mention in the email you’re writing. Kyle VanHemert
On the other hand you could argue that splitting your attention between the compose window and an endless stream of new incoming messages could distract you from actually finishing what you’re currently writing. I personally enjoy the new experience for replies, where I rarely need to edit the recipient list or the subject, but for composing new messages the new style is a step backwards.
Also, some fitting satire from the comments section:
The new Gmail compose is really infuriating - I like using email precisely because it allows for longer, more complex messages. To strip away functionality that is important to many users, for no apparent reason other than an obsession with "cleanness," is just bizarre to me. I'm trying to imagine a Gmail programmer talking to an interior decorator:
Decorator: ...And then we'll put the couch over here.
Gmail programmer: Oh, our data show that people only sit on living room couches 20% of the time. So it makes more sense to keep the couch in the garage, and tell people to carry it in whenever they feel like watching TV. By the way, we put the TV down in the basement. Look for the box labelled with a mysterious icon.
Decorator: Wouldn't it be a lot easier to just keep the couch and TV here, so they're available whenever people feel like using them?
Gmail programmer: Nah, people just have to get used to the new system. (Chuckles) Besides, what are they going to do, move?Chalchihuite