These drills are beneficial learning aides for the student. The drills themselves aren't the problem; the problem is stopping there and not taking it a step further.
In my school we would do defensive drills where the oppoenent would come at you with a single stick and you'd have a single stick or a single stick and knife (you could do it empty handed, but we didn't train it much). This trained "pass and hit"; you hit the opponent's wrist/hand/forearm while either directing or redirecting their attack and then they counter and you keep going back and forth. It's a live drill that throws random attacks at you.
The problem is that it's easy to get caught up in it like a dance. You forget about the subtleties of actual combat and get rused in to thinking that it is combat because they're coming at you fast, at random, and you have to react. But..
- Distance usually isn't accurate. 99% of the time, your partner will be striking from a somewhat safe distance. Realistically, they should be attacking closer
- Even when doing similar drills involving empty hand vs stick defense, when flicking the stick away, they should be going for your legs on the down swing and this never really happens (though proper footwork is drilled in to you to avoid this, if they're at the right distance, it's different. You have to move further and think more).
- If you screw up with the defense, you don't have to worry (99%) of the time about getting thwacked
This isn't the fault of the drill; it's the fault of not doing the drill real enough. When I do it with folks I've taught, I've started to play with this and after years of doing it so-so, I notice how different it feels when I do it right and how much more difficult it is.
When my partner comes at me, he should be closer, and thus I have to react quicker and stronger to do the technique right. When my defense involves a downswing of their hand (thus bringing their stick close to my legs), I need to not just do the right footwork (step back/to the side), I need to make sure they're in range to hit my leg if I don't react quick enough or step away enough.
I think the right appraoch should involve 3 basic steps:
- no resistance
- some resistance
- full resistance
(of course, there are points in between, but this is the basics)
Even at the school I attended, we didn't really do the last one; just lots of the middle one. This lead to bad habits for me which took me something like 10 years to notice and begin to correct (and that's only because of my training philosophy).
Short version: the drills/forms aren't the problem. How students are taught to train them is the problem.