Slipping feeling in 2012 Subaru Legacy

I have a 2012 Subaru Legacy.  I have noticed while driving that it feels like it is hesitating when accelerating.  I can replicate it by driving normally, then quickly accelerate then take my foot off the accelerator.  The tachometer races, as does the engine, then it goes back to normal.  The car does not accelerate.  I have taken it to the dealer twice and they can not replicate it or find any lights or codes.  They say this is normal. I have driven the car since new at 70k miles, regular maintenance, garage kept and this is not normal.  I even videoed, per the dealers's request and had the service manager's spouse (who is a Subaru employee) ride with me and she felt it.  This dealership bought out my dealer that I purchased the car from so now I am stuck.