Lets be honest for a moment who can possibly turn down that offer. (Although, I do wonder, is it scalable? can you use that plan to do $10K on $50K monthly? Or, lets say you really went all in on this plan, can you do $100K on $500K monthly?) I know I'm getting a little bit ahead of myself here, but at 20% per month how far away can freedom really be? Of course 20% a month is equal to 240% a year, and that is without compounding!
As a subscriber to Sheridan, Aeromir and Locke [ so that's my full disclosure ], I have no need to defend/sell one side on the other but am happy to comment with some bit of inside knowledge ... although I have not seen this course or its intro video yet.
Does the course title say you can make 20K on 100K? Does the course title say you can make 100K on 500K? Very clearly it does not. Also, does it say this will happen every month? Although that is not clearly said, I would not assume this to happen every month. Does it say you can compound? No - it does not. Just like Aeromir has a long caveat before all their videos: we are not a broker dealer, we do not know your situation and how much risk you can take, all this is education, I am sure something similar will apply here in terms of monthly risk as well as scalability - each month is different and each level of scaling will give different results. Then from what I have seen of Sheridan: he usually goes for a campaign of trades: close winning trades at 10% (40 times a year), close losing trades at 15-20% (10 times a year) so overall you net 10% X 20 times a year ... still a massive amount but you need the spare change to stand the drawdowns if it happens 4 times in a row - that's your plan and nothing to do with the core trading model.
Now I have taken exactly 2 trades based on Sheridan's formulas - as I prefer other ways of trading - and I have seen maybe 20 videos, and based on all that, I am reasonably sure A) what he is saying is not a misrepresentation - you can probably make 20% on 20K monthly, and B) (very likely but not sure) you can do it 40 out of 50 months and then also may lose 40% (of the trade value=8K) in the other 10 months, and C) he does not advise you to put all your money in this bucket. So over 4 years you run this trade with constant trade size of 20K, you make a profit of 160K in winning months, loss of 80K in losing month, and winning and losing will be interspersed in indeterminate random order giving a cumulative profit of 80K.
Now just assume that your overall trading account is 200K (so that you can spend 10% = 20K in this highly speculative part of the account) and all you are talking about is a gain of 80K over 4 years = 40% = 10% of account size per year. You need to trade (or keep) the other 180K for other more conservative trades or in cash. With that bit of inside knowledge, it does not sound so absurd to me.