Commuter Rail executives promise that 2017 won't see repeats of the on-time performance woes that plagued the system throughout the latter part of last year.

Keolis general manager David Scorey told a legislative committee that a major schedule change and a maintenance backlog caused trains to show up on time only 84 percent of the time in November.

"Now, that sort of thing happening on a major schedule charge. I have a lot of experience on schedule changes elsewhere in the world. It can happen. It can happen and it happened here," Scorey told the Joint Transportation Committee.

Scorey said they've worked through the schedule issues and have seen a notable uptick in performance. Scorey said 2017, as we enter the winter season, will be better for riders.

While hearing testimony from the T's Fiscal and Management Control Board, both House and Senate chairmen criticized the MBTA's management for withholding reports on cash collection and cleaning contracts from lawmakers while taking credit for making the T more transparent.

Sen. Thomas McGee said that it's "important for the public to understand what all that dynamic was," that led to the MBTA's decision last year to privatize it's cash counting operation and to cut spending on janitors. "What the costs were, what the employees were making, what the decisions were made and what those ramifications were," are important, McGee said.

An MBTA spokesman said the documents contain sensitive security information and will revisit the issue when a private collection company takes over the operation.

The MBTAreached a contract extension agreement with its biggest labor group, Carmen's Union, Local 589, last month that saw the T's vehicle operators give up expected raises in exchange for guarantees that their jobs won't be outsourced to private companies. The three-year contract also lays out how the T will streamline its route scheduling system and give bus and subway operators more flexibility over when they work, including allowing for four-day work weeks.

Dealings with the Carmen had become a political flashpoint in Gov. Charlie Baker's administration's ongoing efforts to fix the poorly managed MBTA. When they authorized Baker's plan to set up a new dedicated Fiscal and Management Control Board to oversee the agency in 2015, Democrats in the Legislature also gave Baker the power to privative T services and functions without needing approval from the state auditor. Outsourcing could have spelled the end for many union jobs and over the course of the negotiations, many Democratic lawmakers, who count Labor as a key ally, distanced themselves from the privatization vote.

Both McGee and Straus took issue with the MBTA managers'' repeated use of the term "structural deficit" to describe the condition of the T's operating budget. The Legislature traditionally pays the T an annual $187 million to fill the gap between what the agency makes off it's own revenues and what it pays to keep the system running. Lawmakers praised MBTA managers' success in lowering expenses enough that some of that $187 million could be shifted from operations to long-term projects, but criticized them for characterizing the situation as a "deficit" since the state already fills that hole. The public, the chairmen implied, get the idea that the T is consistently operating in the red, when in fact the state has successfully floated its books for year.