Is Vallado's Revisiting Spacetrack Report #3 still relevant today?

The title pretty much sums it up. I am reading David A. Vallado's Revisiting Spacetrack Report #3, which was published in 2006 and includes source code for the SGP model series. I was wondering, is the code and equations still relevant today?

• I think your question should be adjusted. The answer to "is it relevant" is of course yes, how could it be irrelevant? If you want to ask if it is the final word or if recent changes are such that there is more to be said, then better rewrite your question. TLEs and SGP4 are still backwards compatible in that you can still use old TLEs and old SGP4/SDP4 propagators and get the same good results. You can read through questions tagged with sgp4 and two-line-elements to get more background and some leads on what's changing and what isn't, or leave that for answers. – uhoh Apr 9 at 0:41
• – uhoh Apr 9 at 0:44