Ability to enter SP fading with time?

I'm a bit surprised something like this hasn't already come up, but I looked and searched--I honestly did--and I couldn't find anything like what I was going for, so if you've seen this somewhere...can't say I didn't try ;)

When I first learned about lucid dreams and how to intentionally have them, I was told that WILD was the easiest method and so I went with that.

On my first night of trying it, I got into bed and followed the instructions to just remain still and all that...and within five minutes I truly couldn't move, and I was feeling very light and tingly. Being my first time I broke it off out of fear, but later on in the night I did it again, accidentally achieving a WILD this time. By early morning, I had gone into SP in a very short time at least once more.

Later on that afternoon, I spent time adjusting myself to the then-scary sensations associated with SP/WILD. I'd just be feeling the paralysis creep up my body, but then I'd break it off before it could get everything stuck, since all I wanted to do was get to SP, not all the way to a WILD. I did this over and over in a short period of time, having no trouble at all getting there.

And now we come to where I am today...and it's EXTREMELY hard to duplicate this scenario anymore. Doing the same things as I did then, it takes a VERY long time to even begin to feel SP, and most of the time it just fades away totally fruitless.

So what do you guys think? Can you lose your ability to intentionally enter SP if misused (i.e. get in, break it off, get in, break it off)?

Any suggestions for how I can get back to being a SP inducing machine are welcome as well.

...if only I'd known more about LDs back then... :(

Thanks in advance! I really want to get WILD down...