1) absolutely! that likelihood must be considered and is quite circular in thought. The "expert" generally won't attack with the methods our 'ideal' phase outlines. So we what-if the techniques and attacks to make them more realistic. In what-if-ing the techniques and attacks we inevitably end up in a position found in the ideal phase of another technique and can then return to ideal phase there just to repeat the process if another variable is introduced.
2) I don't think there are any problems with the moves for the attacks they are defending against. The main problem is that the committed lunges, and stabs aren't the "expert attacks". Want to correct something? Where are the slash defenses? Oh that's right, they're addressed in the club techniques with minor adjustments to address the blade. Besids techniques are just vehicles to get the principles across. that whole divert-sieze, control, disarm thing and other meaningless stuff like that
3) When something goes wrong, chosse to do something else. When something goes right, you may still choose to do something else. The majority of weapon defenses have the same trends :
A) the initial moves are designed to disarm the attacker but people continue with the technique "as written" and ask "this doesn't make sense, why am I doing this if he still has the weapon?" Possible answer: because IDEALY he doesn't have the weapon anymore.
B) The kenpo rule is "divert, seize, control, disarm." When a weapon technique fails to adhere to this rule people don't what-if the technique or ask why. There is a reason for the diversion from the rule (pun intended).
4) The Kenpo technique on that post you hotlinked seems to be Thrusting Lance, I've had the unfortunate pleasure of actually using that one for real. Here's how it went.
A) Jerk tried to stab me and I hit his wrist and has groin, he dropped the knife. (Weapon diverted and disarmed no seize and control available).
B) with no more knife to worry about there was no need to manipulate his arm and break his wrist to get rid of the knife and risk a grappling match.
C) Obscure elbow, uppercut, sandwich, handsword, hammer fist (Locking Horns into Detour from Doom) go home to my family in one piece.
In my opinion the technique did exactly what it was supposed do. But there are those that would say "you
had to change it so it didn't work" my response: "I
choose to change things and made it home to my son, it worked fine in my textbook"