My friend, if you don't feel the inclining to contribute when you think you know very little, then you might never get the urge to contribute. For when you still know allitle, you should ask some constructive questions that when answered to you, will help out alot of other guys.
Personally, i didn't see your need to even tell the community you are around here somewhere since you just lurk around and don't talk to anyone hence your absence won't be felt mate.
For when you have a minute, look at my first 100 or so posts, i swear i knew nothing, well not that much and i have never gone for a CS class but atleast i contributed. Worst of all i never had a computer or even internet access so i would save up enough and hope in the computer Cafe and comment on a post or two and go home. Sometimes others questions motivated me to google and understand what there would have been answers then i finally answer them.
So mate, drop the i will contribute after two years when i have attended my CS class attitude, and contribute already. I swear class is just a show but in the wild learn will teach you loads.
So you were not around, won't be around, don't know you well, you won't contribute in the nxt Two year and more, why in the seven hells should i be smurfed by a ghost lurker then?