I haven't had any luck doing that with them in the past. Though they've always been more than happy to approve me for another credit card with 6k+ limits. I'm also a bit skeptical about their CLI process as every time I've called I have been told by CSRs "reviews are done twice a year, and I can't authorize an increase at this point". I've had insurance with them for 10 years, and cards with them for 2. During those 2 years FICO scores have jumped an average of 70 points, and verifiable income has gone up about 27%. Mine may not be the best situation to compare to, but I personally prefer NFCU. I treat them right (prepaying loan balances, never missing payments, treating CSRs like people I like [because I do actually like them], etc.), and they return the favor (offer to get adjusters on the line instead of me requesting, never been denied for a loan/cc/loc/cli, willing to review CC APR's every 6 months to make sure I'm getting the best rate, able to transfer limits with a quick 15 minute phone call). I treat the USAA people the same way, but it seems to me as if they rather you just sign up for something new (pressure for numbers I'd guess). If I wasn't already married, I'd sure try to put a ring on NFCU's proverbial finger. 
as always, just my 0.259 cents.
Sounds like you are thinking about apping?
Just double checking. You are on my list of those I have to keep a close eye on! Lol
Me a vilolator?? Nooo not me!
Really? Surely you jest!