I get your idea.
From my personal experiences with shared hosting providers --- one has this feature but not the other and another has that feature but not the other; one misses this PHP library and another misses that PHP library and these "games" basically never end.
Choosing not to utilize the well-vetted-and-provided information is your choice, but I personally don't think your understood concept of "best practice" for web design is a reason for me to repeat knowledge that is readily available.
You proved my point here with "philosophically biased me personally". Were you originally seeking knowledge or to criticize the way others have presented it? I understand your day job as it's certainly part of my day job too. While I appreciate the advice, I'm a bit confused as to your goals here.
Quite possible and I will take this under advisement.
I personally can't stand those manuals and, as a senior software engineer with decades of experience, believe them to be nearly unfathomable much of the time. 
In the software development lifecycle (SDLC), the staging environment often falls between integration/QA and production. It is frequently used as a "pre-production" environment to perform broader testing of (sometimes experimental) features because it so closely resembles production without actually being production. In Let's Encrypt's case, the production environment has stringent rules and regulations placed upon it that would make such testing and experimentation much more difficult (if not impossible) without a staging environment. Let's Encrypt has graciously made their staging environment publicly available for the benefit of all.
CertSage does provide one specialized functionality for cPanel (certificate installation) and has been heavily vetted in various cPanel environments, but that's where the specialization ends.
CertSage has been proven very intuitive to use as indicated by the very low number of help requests to use it compared to its usership size. I've received "thank you" notes and generous donations for years attesting to exactly such.
What you have declared "wrong" here is a matter of your own opinion to which you are fully entitled. Others seem to believe quite differently from yourself.
My main goal was mostly to describe my own hardship with one passage with ten links and to give my own perspective mostly about that; I did so mostly based on my personal professional attitude for web text accessibility and I certainly didn't mean only to CertSage.
I certainly didn't mean to disrespect your most generous contribution and have done best to share a most minor constructive criticism with not an iota of bad intention and most carefully.
I thank you for your patience and for trying to understand me and of course, for your contribution for us all.
I have no doubts you deserve any donation and even more, for CertSage.
Indeed I respect your kind words, constructive criticism, and the opportunity you have afforded me to exercise calm patience. Take heart in that I feel no direct offense by what you have so forthrightly stated. I fundamentally agree with most, if not all, of the evaluations of CertSage that you have made for I have made a great many of the same evaluations myself throughout the design and evolution of CertSage. I will take the advice you have generously provided under advisement in my continual efforts to address the frequently contradictory design challenges of CertSage. I have realized that though I might disagree with a vantage from my own position, I must accept that vantage's from others' positions are not my own and so I must learn what I can from them. Thank you.