Everything makes sense but this. I'm still baffled as to why this is something that would need to be done.
It has to do with how LTIR rules work. They work a little differently if you have a player on LTIR to start the season. By having the Cap Hits for all of the players minus Vokoun get as close to the Cap as possible, they get more extra cap space granted for Vokoun being on LTIR. Basically, they are allowed to go over by the amount that Vokoun takes them over. So if the cap for everyone minus Vokoun adds up to to $1 million less than the Cap, then putting Vokoun on LTIR only allows them to go $1 million over the Cap ($2 million minus the $1 million in existing cap space). If they have no cap space left, then they get a full $2 million in extra space by putting Vokoun on LTIR.
With 25 roster spots to work with (23 plus two on IR), they did math tetris to determine which cap hits to have on the roster without having to send anyone additional through waivers. That translated to keeping Conner on the roster, calling up Ruopp, but sending down Bennett. Keeping Maatta and sending down Despres appear to be hockey decisions rather than cap decisions, but that does affect the math tetris.
Once the season actually starts (tonight), the rules for LTIR change. So they had do this math tetris for the 5pm roster deadline last night in order to get the extra space set the way it is. (See CBA section 50.10(d) for the full legalese).
Now that the period for setting the LTIR extra cap space has passed, they will do further roster moves to get to their actual starting night roster. Considering Conner and Ruopp aren't even practicing with the team today, but Kobasew is, and factor in that they wanted to keep Bennett close by sending him to Wheeling, but sent Despres to WB/S, and you can pretty much connect the dots to figure out what the next moves will be.