It's a perfectly good fix, most sites have zlib.output_compression Off by default in php.ini
Most likely you have seen some sort of "double compression time out". Some files (settings) of moodle can use for example gzencode() (lib\minify\lib\Minify.php) and for example TinyMCE's compressor using gzencode() had issues with zlib.output_compression already years ago because it was (and probably still is) incompatible with zlib.output_compression.
Some issues are reported to tracker too, for example
http://tracker.moodle.org/browse/MDL-35640
In php.ini you can set it by
zlib.output_compression = Off