I have arranged my system to have the electronics on the front wall between the speakers in three different rooms and it has always worked fine. Fortunately, they have been fairly large rooms where I could put the speakers out into the room at least 5 feet from the front wall. The imaging has been great and I've heard no negative effect from having the equipment between/behind the speakers. The equipment (except for a TV) acts as a diffuser. I also use dowel CD racks which also act as diffusors. The speakers I had for most of that time were Mirage M3si which have rear firing midrange and tweeters for ambiance. I now have a pair of Thiel CS6 which are more directional.
I suspect that the people saying you should never put your equipment behind your speakers are the ones who would much rather have you spend thousands of dollars on commercial duffusers/absorbers/traps etc.
Besides bass management, which a completely different issue, the biggest room problem is slap echo and the decay time of that echo. You can control the slapiness with diffusion and the decay time through absorbtion. Placing your equipment on the front wall just becomes one element of room acoustics that you have to work with to get things right.