Trying to mount mhddfs / osxfuse via fstab
Here is a way to mount osxfuse / mhddfs via LaunchDaemon

Prerequisites:
– existing /mnt/DrivePoolA
– some Volumes (in the example below Test01-Test03 mounted at /Volumes)
– OSXFuse 2.7.3
– mhddfs via macports


Create a file com.oxsfuse.mhddfs.plist in /Library/LaunchDaemons/

&lt;?xml version="1.0" encoding="UTF-8"?&gt;
&lt;!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd"&gt;
&lt;plist version="1.0"&gt;
&lt;dict&gt;
    &lt;key&gt;Label&lt;/key&gt;
    &lt;string&gt;com.oxsfuse.mhddfs&lt;/string&gt;
    &lt;key&gt;ProgramArguments&lt;/key&gt;
    &lt;array&gt;
        &lt;string&gt;sh&lt;/string&gt;
        &lt;string&gt;/usr/local/mhddfs-start.sh&lt;/string&gt;
    &lt;/array&gt;
    &lt;key&gt;RunAtLoad&lt;/key&gt;
    &lt;true/&gt;
&lt;/dict&gt;
&lt;/plist&gt;

Enter in Terminal:  

 sudo chown root:wheel /Library/LaunchDaemons/com.oxsfuse.mhddfs.plist 
 sudo chmod 644 /Library/LaunchDaemons/com.oxsfuse.mhddfs.plist 

Create a file mhddfs-start.sh in /usr/local/

#!/bin/bash

kextload /Library/Filesystems/osxfusefs.fs/Support/osxfusefs.kext
sysctl -w osxfuse.tunables.allow_other=1
/opt/local/bin/mhddfs /Volumes/Test01,/Volumes/Test02,/Volumes/Test03 /mnt/DrivePoolA -o allow_other,loglevel=0,logfile=/tmp/mhddfs1.log,volname=DrivePoolA
sleep 5
/opt/local/bin/mhddfs /Volumes/Test01,/Volumes/Test02,/Volumes/Test03 /mnt/DrivePoolA -o allow_other,loglevel=0,logfile=/tmp/mhddfs2.log,volname=DrivePoolA

Enter in Terminal:  

 sudo chown root:wheel /usr/local/mhddfs-start.sh  



You may store the shell script somewhere else but be sure to adapt &lt;string&gt;/usr/local/mhddfs-start.sh&lt;/string&gt; in the file com.oxsfuse.mhddfs.plist.

After some extended testing in a Parallels VM (Mavericks with OSXFuse 2.7.3 and macport's mhddfs) i got it mounted reliably. And yes, executing mhddfs two times is intended!

You may omit the loglevel=0,logfile=/tmp/mhddfs1/2.log,-part in the shell script - it was just for testing purposes.

Please do some tests with the volumes before using it in a productive environment.