Definitely. But, since steroids are already illegal and since there is no evidence on what their side effects truly are (we know from experience, there are almost zeros studies done, especially on substances like tren, boldenone, dbol, rbol, anadrol etc).
So, in order to these seminar to exist, we must first do studies on each substance, for a period of months, with different dosages. This would take years. But yes, I totally agree with you on the taking a course part. But, it is just not doable.