Argghhhhh this thread is sooo frustrating. I am familiar with roulette on a good enough level, but not when it comes to all the terms. I feel I have something to add, but it might come out wrong using the wrong terms. Anyway, I´ll give it a try.
I basically don´t buy any roulette strategy whatseoever. It´s a wheel with 37 numbers, it does not start somewhere, it does not end, it´s infinity objectified. With that said, within infinity, there is room for any possible outcome from any possible strategy and even if the outcome confirms the strategy 7 days a week, it´s not enough to establish it as a profiting way of playing roulette. I think that if you want to beat roulette, you need to focus on the "not so" infinite parts of it. The table itself, or the bias of each table basically. Now to put this in words, what I mean is that every spin on that roulettewheel, every day that passes by, will make small small micro adjustments to the randomness of that wheel. Over time, some of these adjustments might resonate and after a while you can start seeing some numbers being over-represented in a series of 10.000 spins. If you can spot a table like this, if you always play at the same "live roulette" table and you know they are not rotating every day, betting on the winning numbers should make you profit in the long run, as long as you know what table/wheel you are playing at. This is of course more for the landbased casinos, but it should be possible to apply to some extent even in live roulette online. Also, the way you would be playing here, is extremely boring. Very few and low bets, on the same numbers, over and over and over again, some times missing the first 50 spins without a single win. So you need some bankroll to cover the investment as well.
The only other way I would believe you can actually profit, is patterns in where the number lands depending on where it last landed. Sometimes you can see a repetitive pattern here, even if it´s not identical each time, it can get very close. It all comes down to the croupier throwing the same ball with the same speed, movement and intervalls over and over again. Something the casinos try to avoid happening by changing croupiers frequently. However, if you spot these patterns and start using it to predict the next coming number, a bet on this number and its neighbours has many times given me a really good session.
As for betting strategies based on %-ages and what numbers to bet on etc, I don´t believe any of these works. You can play around with the numbers all the way you want, but in the end, the theoretical winrate cant possibly become more than 0.98 (?) no matter how you bet.