I've had TREN cough before, so that means some worked its way into a vein right? i'm still here.
Often i'll have a jab, and almost immediately get a wierd taste in my mouth, that's due to oil getting into a vein also right. i'm still breathing.
Chances are, you can put the needle THROUGH a vein, and out the otherside, inject 3ml's and as you withdraw the pin back THROUGH the vein, some of the oil will enter the vein just as the hole closes up. I think it is highly unlikely that 3ml would enter the vein. Bearing in mind the vein is under pressure from the blood being pumped through it, so it's trying to piss blood out, not suck stuff in - its almost impossible for the oil to enter it, right?
now, the chances of the tip of the needle ending right in the middle of a vein, and injecting 3ml's directly IV, must be tiny. I know when i aspirate, the pin is wiggling all over the fucking place, tearing muscle up on its way, but to get the pin RIGHT IN THE MIDDLE of a vein, keep it still, and get an amount of liquid in there, that could cause harm, well, it aint gonna happen.