if your goal is powerlifting i would not recommend it.
i used to do 6-10 workouts a week years ago. but that was when i was an endurance based athlete. my work capacity was very high. now that i train for strength i am doing a 3day split with an event day and i surpassed my past strength levels in a matter of months even after a near 4yr lay off of any exercise. now my work capacity is not near as high but we can think specificity of training for that.
remember, you grow bigger and get stronger after you leave the gym. i think of things like this when contemplating whether 1 of 2 theories are correct, the supercompensation theory or the fit/fatigue theory. i am a believer of fit/fatigue but even that one states that you need to recover from a workout. and multiple sessions a day even if only a few times a week may not allow for that to happen properly before you do the next workout.
now if the second one and/or third workout of a short time period is meant for increasing work capacity then i say go for it. if you think it will make you stronger in a 1rm then i say no, dont do it with powerlifting. and this leads me into another point. the olympic lifts that the bulgarians used in their training have no eccentric portion of the lift. saving them from a certain level of muscle damage/strain from training.