Am I wasting money on the theory of Bi-amping?

The issue is half in the speaker, half in the amp.  Lots of speakers have challenging loads in the bass, and lots of amps can perform better with better power supplies.   Notice this is kind of statistical.  I say "lots" and "most." So, while bi-amping may help, it won't always.

When you bi-amp you double the power supply and output transistors, therefore making the amp less sensitive to impedance issues. 

Whether or not it helps you is something you should hear for yourself.  Generally you should hear better defined bass and transients.  If you don't hear that you may as well sell an amp.

My first "go" at this was many years ago when I got my Genesis V speakers that came with an outboard amp/crossover and used my VAC tube amp on top. My next setup was the internally powered Golden Ear Triton 1.r speakers which also "bi- amp" the bass. I recently got rid of them in favor of the Legacy Audio Focus XD speakers that are "bi -Amp" speakers. They have an internal amp in them. I am now in the process of doing this right and have ordered their external crossover Wavelet II which will go between my VAC pre amp and the speakers as well as my VAC tube amp for mids and highs. The Wavelet will then feed to the speakers internal amp and my external VAC amp simultaneously. So far all have worked out for me, yet this final ventures is yet to be determined although it may most likely be the best of them all.

@ibisghost 

Depends on your speakers and your amplifier.  

In my case it was worth the effort in a previous system.  

I had floorstanders with dual 6-3/4 inch woofers that had their own set of speaker termminals.  They had another set of terminals for the 4-1/2 inch midrange and 1 inch tweeter.  The internal crossover managed the signal between midrange and tweeter.  

With my 80 watt integrated amplifier driving the entire speaker using the supplied brass jumpers, the system ran out of power sooner than I liked- sounded strained, harsh and slightly clipping in the midrange and bass punch reached its peak.  

I then used the pre-outs of the integrated to connect to a 150 WPC power amp of the same brand, same gain, and connected it to the woofer terminals.  

I connected the speaker terminals of the 80 watt integrated amp to the midrange+tweeter terminals.  

Wow what a change.  Bass punch and response was incredibly powerful and beyond my needs, never ran out of gas.  The midrange never ever sounded strained or clipped, could crank that system as high as I could ever want.  

So in that case the original amp was underpowered for the entire speaker at the volume level I preferred.  Also since the speakers had a midrange / tweeter setup and had separate jumpers for the woofers, driving them with a separate amp was worthwhile.  

I would never find biamping worth the effort with an amplifier just for a tweeter- they consume such a small amount of power.  I would also not consider biamping a speaker without dual sets of jumpers and having to bypass the internal crossovers.  Opens up a can of worms not worth the effort.   

fthompson251 is doing it right ....   with speakers AND electronics designed with bi-amplification in mind.   If your gear isn't then it's probably a wasted effort 

Depends on amps and speakers.

If you have a 3 or more way where only fairly deep bass can be isolated to one amp, maybe. I think you would need to be pushing your system hard for it to matter.