Grand Central Station Complex (incl Upgrades): 4, 5, 6, S

The 7 had to not only avoid the exisiting IRT lines at Grand Central, but the H&M as well. Mr. Mcadoo had aquired the rights to extend the 33rd street line to grand central. While he never exersised those rights, the IRT still needed to build around his reserved space.

Is that the level of the ESA station at GCT?

An area developer is footing the bill for improvements to Grand Central's 4-5-6 lines. Newsday

The title is a bit misleading; the improvements are more towards the subway and ESA, not the current MNRR GCT. Brief, fair-use quote:

LIRR, East Side Access to benefit from $220M in Grand Central Terminal improvements, developer says

...
Although the developer is spending most of the $220 million to open up extra space in Grand Central's congested 4, 5, and 6 subway station, about a third of the money will go directly toward improvements for East Side Access -- the Metropolitan Transportation Authority's $11 billion megaproject to link the LIRR to Grand Central by 2022.

While East Side Access aims to shorten the commutes of about 60,000 customers, the MTA's plan would have required LIRR riders looking to transfer to the subway to come up from a new concourse to Grand Central's dining course, only to go back down again into the subway.
...

From Crain's

City approves 1 Vanderbilt after developer agrees to make upgrades to Grand Central

...In exchange for getting more square footage, developer SL Green Realty Corp. will invest about $220 million in critical improvements to Grand Central, allowing more trains to run during rush hour on the clogged 4-5-6 lines, which carry more people per day than the entire transit systems of Chicago or Washington, D.C.
...
The most important work will happen on the 4-5-6 platform, one of the most notoriously overcrowded waiting areas in the subway system. During rush hour, commuters often have to watch several trains pass before they are able to squeeze onto one. The main problem is lack of space on the platform itself, which is dominated by numerous thick columns that take up unnecessary space, transit officials say.

"This is the bottleneck to the subway line," Edith Hsu-Chen, director of the Manhattan office of the city's department of planning, told city council members during a hearing last month. "Improvements made to this station would affect the entire line and commuters in the whole city."

SL Green will strip the columns down to the bare bones—slimming them down by about a foot each—and narrow the stairwell to create about two and a half feet of extra space on the platform. That may not sound like much, but on a crowded platform, it could make a world of difference: one more train could run per hour during rush hour, according to MTA estimates.
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All improvements will be complete by 2020 or 2021, about two or three years before the East Side Access project will be finished, Mr. Schiffer said.

The platforms are located in an odd space where the subway moves from under Park Avenue to Lexington Ave. There is a fly-under for the 42nd St. shuttle access and the 7 line below that. Widening these platforms would be well nigh impossible, so every little bit helps. Unfortunately, the long awaited Second Avenue Subway won't help here. Passengers for the Bronx will still have to cram onto the 4, 5 and 6, while passengers for uptown and Harlem would have to take the shuttle to the Q instead of direct service via Lexington. What happens when ESA opens and diverts passengers from the West Side onto the 4, 5. 6?

In the news (from Girl on the Train's favorite publication ): Gothamist

Inside The $220 Million Plan To Improve The Subway At Grand Central
...
SL Green detailed that two thirds of the $220 million—the largest private investment in MTA infrastructure in the city's history—will go towards alleviating overcrowding at Grand Central.

In addition to new stairwells at both ends of the two 4/5/6 platforms, AM New York reports that the developer will also bulldoze the Hyatt Hotel basement that currently cuts into the subway, increasing mezzanine space by 40%. SL Green will also construct two new street-level subway entrances, and increase platform space by removing bulky columns that currently support the Hyatt in favor of a narrower design.

The city says that the renovations will make room for 2,200 more riders every hour at the station, and that the MTA will provide one additional train per hour in each direction to accommodate them. Grand Central currently accommodates about 154,000 per workday.

There are also plans for a new 14,000-square-foot pedestrian plaza on Vanderbilt Avenue in the shadow of One Vanderbilt, which will take up the block between Vanderbilt and Madison Avenues and 42nd and 43rd Streets.

A new concourse under One Vanderbilt will eventually connect Grand Central commuters to the $10 billion, perennially delayed East Side Access project, which will connect Long Island Rail Road trains to Grand Central. Most recently targeted for a Christmas 2022 completion, East Side Access was delayed again over the summer amid a dispute between MTA and Amtrak regarding nights and weekends construction.
...

Image from above article:

What did I say about treating Gothamist as a reputable (LOL) news source?

Gothamist strikes me more of an aggregator/analyser than a new source.

Anyway, lets get to the meat of the story. Gothamist actually linked to AM New York's story here: http://www.amny.com/transit/one-vanderb ... 1.12466831" onclick="window.open(this.href);return false;

On the street level, SL Green will transform Vanderbilt Avenue between 42nd and 43rd streets into a pedestrian plaza. Down below, the MTA’s notoriously congested Grand Central subway complex, which served 160,294 commuters on an average weekday last year, will get upgrades to increase capacity.

That starts with two new subway entrances. The firm will also raze the Hyatt Hotel basement that dips into the subway station, creating 40% more commuter space in the station’s mezzanine.

On the subway station platforms of the 4, 5 and 6 trains, SL Green will build three new staircases, reconfigure existing stairs and, to find more commuter space, remove bulky encasements of columns that rise up to support the Hyatt.

Ultimately, the MTA estimates that these adjustments will allow for the accommodation of roughly 4,000 to 6,000 additional passengers per hour, which translates into running an additional subway per hour along the Lexington Avenue line in each direction.

They're a blog who rips off news from reputable sources...and then when the sources they rip off update their stories they can't be bothered to do the same.

The links show up in my automated Google search, so that's what I go with!