I believe there is new text shown in the Withdraw section of the SwC Poker cashier:
Your withdraw will be slightly less due to Bitcoin network fee. Users pay exact network fee, there is no charge by SwC.
This is correct. For withdrawals, the required network fee will be deducted from the total amount withdrawn. Players will only pay the exact network fee required to complete the transaction. SwC does not charge or keep any fees for deposits or withdrawals.
Can you please announce changes that negatively affect users prior to their implementation in the future. Your failure to communicate changes prior to their implementation has caused outrage in the past with regards to issues like rake.
I would also suggest discussing proposed changes with the community first to see how they will go over.
I would like to point out that NitrogenSports offers 1 free withdraw per week for users who gamble over a certain amount of their initial deposit. Possibly something like this could be a better solution to keep costs down.
You could have users specify the fee and they would like to pay. I realize that something like this may require software development. Maybe you could do something like a cash outs last digit would signify the speed of transaction your user would like to implement. Say a withdrawal of 10,000.01 would signify the user wants the transaction send with a high fee whereas a withdraw of 10,000.09 would suggest that a user wants the transaction sent with the lowest fee possible.
Also the way you are sending bitcoin seems very suboptimal. When the site is paying for fees this isn't a problem, but if you are charging your users the actual transaction fee you should do your best to keep these fees as low as possible. Below is a withdrawal processed by SWC within the last 24 hrs. The user is a regular and was charged the actual network fee. I have converted the transaction to USD values and hidden the addresses to keep this transaction as private as possible.

How to keep fees low and BTC lingo is not an area of my expertise so I will leave discussing how this is a very suboptimal transaction and the possible solutions to someone with more knowledge in this area.