Does Bi-amping really make a difference in sound?


I have really been torn in the past week in how I should improve my Home theater stereo System. I presently own the following gear:

Oppo Blu-ray Player
Yaqin Tube Buffer (w/ 6SN7 Tung Sol Oval plate Tubes)
Cambridge Audio DAC Magic
NAD C-375 Integrated Amplifier
PSB Synchrony Two loudspeakers
Nordost Red Dawn Ics
Audioquest VDM-X Digital Cable

An experienced audiophile and design engineer who designs speakers and custom electronic gear has told me that in order to improve my sound drastically I need to Bi-amp my speakers. Since PSB speakers have separate crossovers for the tweeter/mid and bass, that I could take advantage of this and bi-amp them and really make them sing.

I was told that I should buy a another amplifier and use the Pre outs of the NAD C-375 Integrated amp and even tailor my sound by selecting the appropriate amp with the same power wattage.
I am thinking of getting an NAD C-275 or the Vincent Audio SP-331 Power Amp to connect to the Pre outs of my NAD C-375 and bi-amp my speakers with two sets of Harmonic Technology Melody cables running shotgun to my speakers.

I also plan to upgrade my digital cable to the HT Digital Silver cable and maybe the HT Silway link Silver to my DAC to NAD C-375 connection over my present Nordost Red Dawn.

My dealer friend disagrees with my approach that bi-amping will improve my sound as he said he conducted a similar setup with the PSB Synchrony Ones in his store and did not hear any differences. I am wondering if he is just wants to steer me in the direction of getting a Rogue Audio Preamp and NAD C-275 combination, which I have considered as well.

Any expertise and advice in this situation would be greatly appreciated. I unfortunately cannot tryout these situations or go listen to them in a store due to my location and have to rely on people’s advice.
rlh157
Post removed 
Thanks all, and FYI, I did look up a few posts on the topic of bi-amping on several websites, and saw how controversial the topic was, which led me to want to get opinions from Audiogon members as well, and information about how to improve my audio system. Your comments help re-affirm my thoughts on the matter, but I thought some folks would also give me feedback on my choices of amps. (i.e.) Whether they felt the Vincent SP-331 Amp was a better choice over the NAD C-275, and whether they thought I had some synergy issues.
I think biamping means 1. using your amp twice a year or 2. not caring much about specific male/female connections.

It does seem like a lot of trouble for home stereo (if you have a 6,000 square foot listening room with gigantic speakers, certainly biamp), and insults all those fine engineers who designed your crossover filtering, although it rewards the sales people by using twice as many amps. I was told by the dude (Alan Yun?) who designed my Silverline Preludes to not even "bi wire" 'em...less coherent he said. I ignored his advice and after spending time in my wire museum with my heat gun and solder I discovered...well hey now...he was 100% correct (he was talking about the Preludes specifically, and I have a friend who uses these biwired and loves it...so who knows?). But I do now have an extra set of perfect wires. Biamping is great for efficient (read LOUD) pro PA stuff because you get more bang for the buck for large venue purposes...otherwise...meh...although it might double your hobby time fun!
I did exhaustive research online prior to posting here on this same topic a couple weeks ago. The problem is there is so much conflicting information that you never really feel like you know what the right answer is. So us newbies to this hobby post here to get expert advice from you 'old-timers'. :-)

Look at it as a compliment that we seek your expert advice, as opposed to an annoyance.