Regardless of how the afterblow is implemented, the terminal effects of swords cannot be rendered at all in a training environment. You can't know if your cut has really been effective (as far as I gather it's real easy to mess up a cut). Your thrust does not enter the body and so the distance cannot be closed in the same way. Your blade cannot get stuck. Your buried blade does not impede the motions of your opponent. And so on and so forth...

Just looking at rapier texts we see thrusts that enter one or two feet of blade into the opponent, some that advise running him through up to the hilt. You can't do this with a training blade, the bend account for 4 inches maybe. This distorts the fight, distorts the afterblow, but then if you do no afterblow it distorts the fight too... So yeah, compromise :)

Regards,

The other part of it is, there is not really a lot of downside in assuming an after blow is possible and protecting yourself from it, even though it may be very unlikely.

Another fact worth noting is that while double/simultaneous hits were commonly (and rightly) disparaged in European swordsmanship throughout the ages, they were as common as heck in real duels and swordfights. Otherwise, I guess, the masters wouldn't have had to caution their student-fencers so sternly against them. So while the sportification of fencing has led to an unfortunate development in the increasing acceptance of double kills as long as the winning fencer scores a fraction of a second before the other, well . . . maybe we need to sit back, take a closer look, and remember that it wasn't all that unusual for both parties in a swordfight or duel to walk away with injuries, often inflicted (near-)simultaneously against each other.

That is, when they had swordfights at all....