"The federal Pension Benefit Guaranty Corp., which insures these pensions, says that some 10 percent of multiemployer plans — covering about 1.5 million people — are in such financial trouble that they are likely to become insolvent. The PBGC estimated that its fund insuring multiemployer plans will likely run out of money in eight to 10 years unless changes are made.
argued that these distressed plans need the ability to cut retirees’
benefits so pensions can survive longer.
and other consumer advocates argue that these pensions aren’t in
immediate danger of insolvency so there is no need to rush this drastic
measure without considering alternatives,
such as scaling back on optional benefits in a plan or providing the
PBGC with greater funds and the authority to intervene earlier.
Advocates also worry that this move by lawmakers might someday open the
door to similar pension cuts in other plans".
source: http://blog.aarp.org/2014/12/16/those-pension-cuts-and-what-you-need-to-know/ via @aarp
So why the cuts--its about stock dividends. When reserves can be cut, that chunk of cash goes into the company's "income" improving "performance" and dividend values.