I personally think all these gambling strategies are a bunch of crap. I have yet to find one strategy that are 100% foolproof. I have trawled the Internet for years to find a strategy that will work 100% of the time and they all fail eventually.
If we are looking for a strategy to beat the house, then we can only find one piece of advice. Quit when we are winning and never come back. If we do that, we can say we beat the house because we pocketed the winnings. But the moment we come back we might need to find something that will guide us to reduce our losses because every gamblers know, in a marathon play, no one will beat the house.
The guides stated are just a guide to minimize losses, get familiar with the game by knowing the statistics, changes, triggers and more. Coupled with it are the bankrupt reduction advice like Bankroll management, stop losses, limit losses and eventually quitting or taking a break.
There are too many "random" things happening with gambling... like your RNG and your client/server seed ....and all of these things are used to determine the outcome of each individual bet.
True that gambling is all about randomness but one thing can't be random and that is how we manage our bankroll and how much we are betting each round. These are the area where we have full control, and if we don't want our bankroll to get busted completely, applying some advice on the list will help us do it.