One thing I have drilled into my students over the past 30 years is that, if they are ever attacked one day, it is virtually guaranteed that their attackers will be bigger and stronger than they are. (And if not, then expect that there will be multiple attackers and that they will be armed.) Common sense testifies to the truth of this—when, if ever, did a smaller person attack a bigger person? Never, unless there were extenuating circumstances, such as a desperate defence or a battlefield conflict, or where there was a hidden advantage (such as concealed weapons).
When we consider this in a calm moment, when not under pressure, of course it makes sense. The catch is that I have found this basic truth taught only rarely, if ever, in martial art training that I have witnessed. Typically, it is not mentioned at all. Perhaps it is assumed that martial art students understand this, but the problem is when the students have had little or no experience of this kind of situation.
(To be fair, with the increasing accessibility of instructional videos on martial arts or self-defence, perhaps this feeling of rarity is no longer valid … but the point is worth emphasising.)
Think of any combat sport situation; competitors are separated into classes, typically by weight and sex, and then sometimes by other factors, such as rank. When, if ever, do we see someone who is 60 kg competing against someone who is 80 kg? When, if ever, do we see men and women competing against each other? When, if ever, do we see adults and children competing against each other?
Size, strength, and other physical factors will have an overwhelming impact on any form of physical hand-to-hand conflict, and anyone seeking to learn a martial art for self-defence must remember this at all times.
Do not be lulled into a false sense of your own capabilities, if all of your training (or competition) has been against people of your own size and strength. Philosophically, I suppose, this risk is one potential drawback of martial sports. Conversely, it is a potential drawback of non-competitive martial arts that there may be low or otherwise unrealistic amounts of conflict pressure on the students.
No system is perfect, but as a martial art instructor, I see it as my responsibility to prepare my students as best possible for a real assault situation—not just in physical technique or other physical factors, but also on the intellectual and emotional fronts. A real assault is not just a physical event.
All of my students will remember: “If you are ever attacked one day, your attacker will be …”