Your probably not reading this, because you are done; but I am gonna say it anyhow cause I am stubborn.
I am frequently compaired to granite in denseness, the words of your post implied even to me, that you felt that the level of combat of us nihonjin is beneath what you expect. That is offensive, who are you to judge us?
Now aside from the semantics and who is offended...
SCA fighting as any (including knights and uberdukes) will tell you very much favors sword and shield combat. The ruleset ensures this.
1. Shields are indestructable... No matter the weapon, nothign you can do will eliminate someone's shield, historically certain weapons were noted for disabling shields, we have no provisions that simulate that. (Hmmm maybe contact cement on thrown javlins/spears??... nah)
2. Shields are involitile... You cannot grasp or kick your opponent's shield, you are not allowed to entangle it with your body, the effectively removes 75% of your ability to control your opponents shield... On the plus side, they cannot shieldpunch you
3. Polearms can only use one end to strike with... this reduced it's effectiveness by about 30%, while historically those shots may not be telling blows, they were used to control your opponent to ensure positioning of them and yourself that a telling blow could be delivered with a lethal section of the weapon.
4. Knees and below are not valid targets... this effectively eliminates alot of the choice targets.
5. We cannot grab, trip, entangle, or strike our opponents with our bodies... Again, this limits your ability to control your opponent.
6. You are not allowed to strike an excessive shot (to overpower the shield)... Striking so hard that their arm goes numb behind the shield or it is beaten down or away so forcefully they cannot respond to your next blow in time again is a limiter
This combination of prohibitions removes the most common and effectve strategies to defeat a shieldman.
Currently we are left with:
Controlling your opponent's shield with your weapon
Controling your opponents shield with your torso or shoulder (pressing into the shield as if you had oen yourself is acceptedly legal as long as you do not strike it.
Halfswording - this is very very promising, it is dirty underhanded and sneaky... I love it, I am discovering new "tricks" to use all the time now, and I feel it does help considerably to close the gap.
In nearly 20 years of fighting sca now (oh god) I have learned that a single two hand sword (not greatsword) will never win against sword and board if the single sword does not control the tempo of the fight. If I control the tempo of the fight, I succeed in delivering a killing blow to my opponent (note, this does not mean he does not... double kill)
I know quite a few guys that fight very similarly to me, but are lacking the physical difficulties I have. A large number of them are very accomplished fighters, a decent number of them are knights, and handful of them are dukes or counts. (oh and a vicount)
I find it interesting that I have fought these guys with greatsword and polearms and can give a decent showing, though when both of us have then gone on to face the same sword and board opponent, it usually goes about 3-5 in the shieldmans favor for them and 2-5 for me.
The ruleset is not against nihonjin, it just favors S&B over all, nihonjin are just particuarlly handicapped since historically we lack the S&B advantage.
Want to improve your single sword against shield game?
Be agressive, blatantly ignore your opponents personal space bubble, invade it, try to crawl into his armor with him... then his shield becomes yours
Remember though you are weilding 3 or more feet of lumber, it only takes an inch to kill him (well if you have a thrusting tip) If you play the range game your gonna spend alot of time running away, and in that you are actualy only responding to the tempo of the fight, not controlling it... For they are deciding when you move, not you controlling when they move.
It takes thousands of hours of practice in order to develop the trick of making them charge and retreat, that is also one of the reasons I screw up... I'm too busy controlling them I forget to position myself adequately to take advantage of what I make them do
-Takeda