I'm not exactly sure how to link the buys to the PC. What I generally do is keep the buy and sell quantity in lots of 100's, so that if I have 1000 shares or less, I'll sell 100 shares, and once I get to 2000 to 2999 shares I sell 200 shares, at 3000-3999 I sell 300 shares... etc. I used to double the buy amounts, just as you said.
You have a memory like an elephant. I'm not currently holding ADCT but if you keep crying about how badly it's doing I might buy some to keep you company. I always used to buy the ones you were selling, but now I try to remember not to do that, and to buy the ones you're BUYING.
Linda