*Update 2/22/16* I’ve tried reproducing the problem with the XF 50-230mm for the past several days on both my X-T1 (with the new firmware 4.30) and my X-E2 (with the new firmware 4.0) and have had little luck making it happen (but it still happens occasionally but very infrequently now). It looks like the firmware updates also included some undocumented tweaking that alleviated this issue. (Yeah!)
I recently purchased a used Fuji X-E2 (running Firmware 3.0) and noticed that it did not have the far focus issue (as badly) that my Fuji X-T1 had when using the 50-230mm at 230mm. At times, it would hunt and not be able to lock focus on something that it could easily focus on at 210mm and below.
“Why would that be?” I thought, and quickly realized the key difference between the cameras — macro mode.
X-T1 firmware 4.0 removed the need to select macro mode to focus on near subjects. X-E2 Firmware 3.o still requires the macro mode selection. With it off, the X-E2 locks focus right away at the long end of the 50-230mm (at least most of the time in good light).
Unfortunately, I have not been able to find a setting in the X-T1 for macro mode buried deep in firmware 4.0, but at least now I know it should be fixable by Fuji.
*Old update* Firmware 4.0 for X-E2 has the same auto macro mode of Firmware 4.0 for X-T1. I’ll do some testing to see if the issue duplicates itself.
*Old update* X-T1 is also getting a firmware update when 4.0 for X-E2 is released.