The latest episode of DDOCast ended up spending an entire hour discussing a proposed change to DDO's two-weapon fighting system. There's an interesting philosophical question here on how to balance the need to fix server issues and game imbalances against respecting player investments in the way that the system has been run for years.
The change... and the other target
Apparently, someone implementing the combat system back when the launch level cap was 10 decided that it would be a cool idea to have the server run a second "physics check" 0.15 seconds after your mainhand attack to determine whether the enemy had wandered out of range before you swung your offhand weapon. Because of the comparatively low level cap, players were only able to get so many offhand attacks to begin with, so no one noticed.
As time went on, however, the cap moved up to level 20, and Turbine added additional classes (Monk) and prestige enhancements (Ranger Tempest line) that added many more offhand attacks. Moreover, the way the math works out (in part due to the pen and paper rules), the full two weapon fighting line turned out to be hands down superior DPS to the alternatives (primarily two-handed weapons). Suddenly, everyone was swinging two weapons and getting tons of extra attacks. This meant lots of extra and largely unnecessary calculations for the server to process, and apparently has gotten so prevalent that it actually causes lag in raids.
To reduce server load, Turbine is proposing to remove the second physics check, and revamp the two-weapon fighting system into something more closely resembling a crit or a double attack percentage. The reason for the controversy is that this change will apparently - and INTENTIONALLY - decrease the DPS of two-weapon fighting.
Is the right call wrong?
Personally, I won't shed a tear for two weapon fighting. The stats requirements for the feat line require some unpleasant building choices. Dexterity is not a useful stat for many classes, but failure to spend those points means permanently and significantly reduced DPS potential. Two-handed weapons should be a viable alternative for characters who are not going to pursue the full two-weapon fighting line, for whatever reason. The fact that this type of change also fixes a poorly-coded mechanic that was causing server issues makes this a no-brainer.
However, I also recognize a sticky situation here because the current state of two weapon fighting is not some new tweak from the most recent patch. The game has been balanced in favor of this combat style for a long time, and many players (even myself, in the mere two months I've been playing the game) have made the decision to pursue the style based on that reality.
How many characters with months or years of investment have been built around a combat style that they might not have chosen if they knew that the long-term goal was for parity? Is it fair to players - some of whom have paid real money for Dexterity enhancing tomes to meet the stat requirements - to turn around now and say that they should simply rebuild their characters (lesser resurrection tokens also available for real money in the DDO store, or via more time-consuming in-game means)?
In the end, this is the correct business decision - it solves a technical issue and a quirk of the character builder that was, frankly, a bit irritating to this particular new player. Very few players will actually quit playing the game over this change, and some may even spend additional money on respeccing or re-rolling the new flavor of the month when the dust settles. This makes the question of whether this type of change is sufficiently large that it should not be made to a post-launch game (see also, Champions Online's notorious launch rebalancing efforts) somewhat unfortunately moot.