I just started woking about 3 months ago and have been studying it non stop. I also agree with the 'stirfry to the sky's edge' book. But I think your problem is probably not enough heat.
There's only so much you can do when you are cooking on a home gas range. Make sure you are using FULL heat. Cast iron is fine but let it heat up all the way before you put anything in it. Try using peanut oil if you aren't already. Also, don't overcrowd your wok. Try cooking a tiny baby size serving worth of food and see how it tastes. If it tastes different/better, that means you've been overcrowding your wok (it doesn't take much!). If you're not using a chinese jet engine for a burner, don't stir your food too much... Let your wok catch up to you so you can get a nice brown sear. Make sure you dry your meat and vegetables before you add them to the wok. Otherwise, it will steam your food instead of searing it. Also, try a flat bottom wok instead of a round bottom (even if you have a wok ring). I find the flat bottom woks sit closer to the fire and therefore get hotter.
I eat A LOT of stir fry... I make this chinese brown sauce once per week and keep it in my fridge:
You could also try blanching the vegetables in water (or oil) and add them to the wok at the very end just to get covered with sauce.
Also, check your ingredients and make sure you aren't substituting something that doesn't work. For example, light soy sauce is not the same as dark soy sauce.
What exactly are you making? Is it one particular dish that doesn't taste right? Or is it all of them?