Here's a question:
I have heard from people not to drop your knee unless you plan on putting it on the ground. They say its a bad habit? Anyway I have this mentality now that if I lean in I can't pull my knee off the bike unless I plan on getting it to the ground. judging from what I have seen here I assume that's not true?
My take on your question goes back to the question of where you are riding. If you're riding on the road, then you really should never be out there putting a knee down. Riding like that on the road is risky. I know that's a personal opinion, but it's unsafe to ride on the road like you'd ride on the track.
Regarding it being a bad habit or not, lots of people have various opinions about this. I'd be more inclined to say that the majority of the people who ride ( like idiots on the road) like that, put a knee out because they think that it looks cool but have no concept of what it really means to attempt to do that. However, if you're taking your bike to the track, it can be very good practice and help you as Charles said to get a better feel for what it feels like to start to move your body in that direction.
You have to keep in mind though that throwing a knee out is about the last thing that really makes any difference in getting your body into the proper position. If your body position is good, all that you will need to do is literally "drop" your knee. If you're pushing it out, you're not in the right position. And keep in mind that you
can get to maximum lean angle without ever putting a knee down if you're in the proper position. Exercising the practice is only going to help you if you're working on the whole overall position (arm, elbow, shoulders, back, hips, feet, and knee). If you know anyone who's skilled and not out to "hot dog" around, ask them for advice, to follow you, or to take pics of you as you go through turns on the track. Pictures are hugely valuable to help you see your position and mark the areas where you need to refine your posture. If you're feeling nervous or tense while working on your position, take a deep breath and release it before you move into position and relax. You'd be surprised at how many people forget to breath.