NYtimes reporter John Broder wrote his rebuttal to Tesla's shared data logs. John put his experience down as why we should believe him.

Since 2009, I have been the Washington bureau reporter responsible for coverage of energy, environment and climate change. I have written numerous articles about the auto industry and several vehicle reviews for the Automobiles pages. (In my 16 years at The Times I have served as White House correspondent, Washington editor, Los Angeles bureau chief and a political correspondent.)

Wired covers this rebuttal.

Times Reporter Disputes Tesla’s Claims, ‘Cannot Account’ for Data Conflict

BY DAMON LAVRINC

02.14.13

8:24 PM

…

New York Times reporter John Broder responded in detail Thursday to Tesla president Elon Musk’s data-driven takedown of Broder’s review of the Model S sedan. And it’s becoming clear that in the credibility battle between a veteran reporter’s notebook and Tesla’s hard data, data has the edge.

I really like the cruise control explanation by the NYTimes reporter.

Musk disputes that Broder turned down the heat, but as Broder points out accurately, Tesla’s logs show that he did just that. But the logs also show that Broder never cruised as slow as 54 miles per hour, nor did he later slog along at 45 miles an hour in a desperate effort to reach a charging station. Broder’s response Thursday relies on his memory, and some shoulder-shrugging.

I do recall setting the cruise control to about 54 m.p.h., as I wrote. The log shows the car traveling about 60 m.p.h. for a nearly 100-mile stretch on the New Jersey Turnpike. I cannot account for the discrepancy, nor for a later stretch in Connecticut where I recall driving about 45 m.p.h., but it may be the result of the car being delivered with 19-inch wheels and all-season tires, not the specified 21-inch wheels and summer tires. That just might have impacted the recorded speed, range, rate of battery depletion or any number of other parameters.

Wired jumps on the cruised control issue.

That strains credulity a bit. Modern cruise control systems generally maintain vehicle speed even on downhill slopes. They aren’t prone to a 15 mile per hour speed boost.

And the Tesla tire issue? Uh, check out the tires size. With the change of 45 to 35 aspect ratio. The 19" wheel has 751 revs/mi. the 21" wheel has 749 revs/mi. No difference. But, that makes no sense how can a 19" wheel and 21" wheel have the same speed? Because aspect ratio of the tire. The 19"/21" is the rim size, not the diameter of the tire.

19" aluminum alloy wheels with all-season tires (Goodyear Eagle RS-A2 245/45R19). Note: optional 21" wheels come with Continental Extreme Contact DW 245/35R21 high-performance tires

Wired closes with the point of the debate.

But what this grudge match is no longer about the Model S’s suitability for road trips. It’s about old school reporting, based on note-taking and memory, peppered with color and craft, versus the precision of numbers and data. And the Times is now obliged to address it on those terms. Because in the end, Broder either set his cruise control for 54 miles and hour, or he didn’t.

It will be interesting how reporting gets changed when data loggers are more accurate than a reporter. This can make for dull uninteresting news. But, data is going to most of the time be closer to the truth than a reporter who thinks cruise control varies by 15 MPH and 19" vs 21" wheels would explains errors in speed indicated.

BTW, I believe in data logging in the car. I have data logger connected up to the OBD port on mine. I use it for tracking mileage for business. But, once my kids start driving I'll be able to see their speed, brake deceleration, acceleration, throttle position, RPM, distance driven.

Times Reporter Disputes Tesla’s Claims, ‘Cannot Account’ for Data Conflict