I don't have enough knowledge to fully elucidate the topic at hand. What we do know is that cholesterol and hormones go hand in hand and when hormonal profiles are altered, cholesterol levels are as well. For instance, low levels of estrogen are known to skew the cholesterol profile to a more negative balance. This is one of the reasons overusage of an AI on cycle is a bad thing.
We also know that cholesterol is made in the liver and oral steroids cause very specific changes within the liver that harm the ability of the organ to produce HDL and get rid of LDL within the body.
Here is a solid article discussing how IM and oral steroids can affect cholesterol values.
Having said that, newer science shows us that particle size of both HDL and LDL is very important, much more so than specific HDL and LDL total values.
http://www.berkeleywellness.com/healthy-eating/diet-weight-loss/article/cholesterol-size-matters
http://www.athero.org/commentaries/comm564.pdf
https://www.sciencedaily.com/releases/2012/07/120711210058.htm
There are studies and articles that explain the differences between the particle sizes and also how they might affect us differently.
https://www.bostonheartdiagnostics.com/science_portfolio_map_test.php
https://jeffreydachmd.com/2018/02/ldl-cholesterol-particle-size-and-number-what-gives/
The testing methods for specific types of HDL and LDL particles is more involved than standard total blood values.
http://www.jlr.org/content/42/8/1331.long
https://www.spectracell.com/clinicians/products/lpp/
As far as whether larger HDL particles can "hide" from a basic test, I'm not sure. I wonder if what he was referring to was the specifics of HDL and LDL. Maybe the video was discussing lower HDL levels not necessarily being bad because training and diet changed the specific particles sizes within the HDL profile and therefore the lower number matters less as the profile itself is better.. We do know that people with "normal" cholesterol values often suffer from heart disease and this "newer" science may help to explain why.
We also learn everyday that us human beings are only as smart as what we just found out and 1000 years from now our ancestors will laugh at our "technological genius" and science knowledge.