What about Gradient Lag?

DCR Comment.  Like most of us we're well aware of his review and the comments.  He's overall quite dismissive of gradient lag

"As far as my recent 1040 test, I went out about 10 days ago and found it wasn’t much different than my 1030 Plus test. I did longer rolling hills, short hills, hills with cobbles. Everything I could find (which, is very limited where I live)."

The issue existed with the 1030+ (which is how this thread started)

And as he admits he doesn't really live in a hilly area 

No , he compare1040 with 1030 + but  oyh have same problem , 

Its sowftware problem

Garmin fixed this problem in one beta , but when they release the final version, then, again same problem

Why do you guys downvote the possible technical explanation of the problem that hard? It would be really nice to get your assumptions and now just downvotes.

But sure, looking into it, reading about technology making assumptions is much harder than complaining.

It's got three downvotes.  Probably from the people who keep defending Garmin and saying this issue doesn't matter.

I'd like to suggest that anyone who does not have experience with the pre-30 series Edge devices has no point of reference/comparison for the current 30 and 40 generation "grade delay" performance. There is a dramatic riding experience difference if you ride in rolling terrain. My assumption at this point is that the barometric hardware in this generation of products has its reporting interval baked into the hardware. Otherwise Garmin could easily give us a grade over x time or distance choice. It is disappointing that Garmin will not simply state that the current grade reporting is fixed by the hardware. I was hoping the introduction of the 40s would have provided a fix. 

I mean, they explain how the hardware works. Each measurement has a variety of 6m. A measurement happens every second.

Now you can include speed and distance travelled and do the math. I explained it on the page before.

Different software (versions)?

You can "Splain" all you want. Garmin needs to "Splain." Recent versions of Edge devices do not have the delightful real time  grade experience of previous ones. That is a Garmin decision they are unwilling to "Splain."

Isn't this completely against your explanation (which I verified and it's completely agreeable)? Shouldn't a difference with previous Edge models be explained by a different barometric sensor? Also, I re-read Garmin statement and there could be different ways to read it. They state the accuracy can be +/-3 meters for any given reading, but we do not know if the sensor accuracy can float that high for any subsequent reading, they might mean that for a reading it might measure 3 meters more, but the reading after 1 second can still measure 3 meters more. There are also way to mitigate false readings by knowing statistically how the sensor performs, human climbing limits and smoothing alghoritms (that don't mean wait 15 seconds between readings)