If you've got 8-ohm speakers and an amp that's designed to be bridged, why exactly is it a bad thing? Just what's wrong with turning a 125W stereo amp into a 400W monoblock? Will you hear something such as noise and/or distortion? Will you shorten the life of the amp? Will you likely overdrive your speakers?
You double the distortion (0.5% THD suddenly becomes 1.0% THD) and you quadruple the noise floor (raise noise by 6dB). You also cut the damping in half.
For High Fidelity, all of these things matter. While it is fun to have 400 watts of power over 125 watts, getting it through bridging means making the performance at 1 watt much worse. Some amps can handle that without any problem because they are so good to start with, but why bother risking it unless it is absolutely necessary?
It is my belief that having lots of available power is vastly overrated for 95% of the systems installed around the world. The greater importance for nearly everyone is the performance in the 0.01 watts to 10 watts. Having the higher peaks is critical, but not more critical than having the best sounding first watt.
For over 15 years I've been working for Dell, so anything I say about computers, mobile phones, printers, networking gear, or anything Dell sells must be taken with a grain of salt.
In a more literal approach, bridges are expensive to build and maintain, so, why build a bridge?
Congress shall make no law that applies to the citizens of the United States that does not apply equally to Senators and or Representatives, and Congress shall make no law that applies to the Senators and or Representatives that does not apply equally to the citizens of the United States.
No no, wrong application:
"I must obey the inscrutable exhortations of my soul. ... My mandate also includes weird bugs." - Calvin (& Hobbes; 3:353 compl. ed.)
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