Tinting my paint job

Im thinking if this is possible...i love my cars colour, metallic blue....but I wont it to be darker...now instead of repsraying im told i can get a job done where clear paint gloss is mixed with a tiny amount of black paint and the car is resprayed, so it's in effect tinting the paintjob.

Is that actually possible?

IF so im going to get it done...

yeah, its a nice idea, but i heard if the gloss is of not so good quality like the toyota's had on their trecel, the gloss would peel off. and leaves u stranded ugly. so see the price bwt the gloss and a better paint. if its not like 200 bucks diff, go for the paint itself. takes the worry off of u.