This is interesting, but this is a bit more hackish than simply re-rolling the dice. Most people would just reroll.

My personal opinion is that dice-hacks should be done to reduce the amount of thinking necessary, not increase it while producing a slightly better result.

I designed a role-playing system once based on the median of 5 d10s. That worked pretty well. It generates a similar bell-curve distribution to the one you get by adding dice, but doesn't require mental arithmetic with large numbers (e.g. 5d10 involves a range of 5-50). I think m5d10 is better than 5d10 because it's easy to develop a feel for "difficulty 7" vs. "difficulty 8"... whereas if the numbers are 37 vs. 38, it gets to the point where 1 point doesn't mean much, and the numbers seem completely made up (which, of course, they are, but they shouldn't seem so).