yes. vary technically impressive, and creepy

there not violin strings... most violin string are to short to string onto a viola. and given the range of pitches he is using there would be no point. if you want to play higher pitches you can your hand up towards the body of viola/violin. what your hearing is him playing in 3rd or 4th pos. on the A string which gives him the same range of pitch a violin would have with the left hand at the end of the neck on an e string in 1st pos. The range of the two overlaps in this way with the exception of the 5 lowest notes a viola can play and the 5 highest a violin can.