This is completely a non-issue, the majority of people are on the main builds and you can specify in your program what firmware and hardware it requires so that it doesn't show up for people that can't run it. I'm not too worried about developing for the 3 people running Bub's AOSP Magic "Original" v 0.3.3. Fragmentation is a boogie-man and nothing more.
The industry doesn't like to change and switching a system that has worked for years is a big process. In a big organization the decision making process for a change of this scale can take years.
Also many places are so technically illiterate that something like this is akin to magic.
It really depends on the system, the problem and the people involved. The system we run where I work has changes put into it in production daily with turnaround times anywhere from an hour to several weeks depending on the change. We have some customers where a fix can be worked on and implemented over the course of weeks due to testing and they have no problem with that and we have customers that expect things to be fixed later today.
The real question to ask yourself and your team is is it reasonable in your product or system to be able to turnaround something that fast?