Roger on'na Deceptively Addictive!!!
Scent...I used to cook-in my scent oils, but not anymore. Plastic Baits will absorb Scent Oil. I drop scent in the bag before I drop the baits in, which helps the baits settle and helps me get them straight. After a few days You'll notice the scent oil "going away"...it's being absorbed. Once it's absorbed, Your baits are scented.
I read, on another forum, that Your scent oil (stabilizer, as well) will "evaporate" off while Your plastic is liquid/hot, so cooking-in scent will waste more scent than it's worth.
Also, effective scent oils are natural oils, and too much natural oils cooked in the plastic can go rancid and cause Your baits to turn cloudy/stinky/oily/nasty. Emulsifiable Oils are the oils that can be smelled and tasted by fish, and these oils are natural, so if You are cooking Your scent in, do so sparingly.