Bro,
Nobody with any common sense is going to agree with you on this. Even if you changed the pin before the next inject, the gear has still been exposed to the open air inside that syringe for a long time! And if this dude is injecting properly, then he is also asparating when he sticks. What if he draws in blood?? And don't think for a second if you don't draw in blood, you're just pulling air into the syringe! Either way, unless you live in a steril plastic bubble, a certain level of contamination has occured as soon as he takes that syringe out of the steril package and draws the juice from its vile or amp. You are just given this dude bad advice..bottom line!
To the one who started this thread.. Don't fuck around splitting 250mgs. Just shoot 250mgs every three days for ten weeks and take your dbol. You'll thank me for it later.