Pro Audio Speaker Wire Fail - Story/Question

I have been the leader of the audio visual team at my church for the past several years. The team consists almost entirely of engineers (the one exception is a computer nerd); however, none of us have any prior pro audio experience and all of the equipment, setup, and connections predated all of us. The equipment was all be pieced together over time by well-meaning yet mostly uninformed people. I have slowly been working my way through the system as I learn more and more. A few years ago we cleaned up the existing cables and removed piles of cables that were only connected on one end or in some cases not at all. Other cables were super long so we visually cleaned things up significantly by spending a few hours coiling up cables. I've finally just about replaced all of the old cables with new stuff from monoprice and we also removed piles of equipment (mostly sources) that would never be used again. The unused equipment and cables were a literal pile that one of the members hauled away in several lawn tractor trailor loads.

I have been very unhappy with the systems performance and sound and last week discovered that something wasn't right with the main speaker wiring. Yesterday, we dug into the setup and rewired the two main speakers to be in stereo with connections to seperate amplifiers that are in bridged mode. We also went through the entire system to correct the gain structure (it was pretty much the opposite of what it should have been). Now we have a great sounding system and we actually have signal levels registering on the board and processor. Previously, we had to have the amplifiers turned all the way up and know they are running around 1/4.

What propted us to get things corrected was finding out that the two main speakers were wired to the amplifier using a single 14 awg wire even though there were two running from the amplifier to the speakers. Now we have two stereo connections even though they share the same mono output from the board. Even after removing the spider web of connection at the speakers we have no idea how the speakers were intended to be connected previously. Each speaker is setup for single or bi-amping so there are four terminals on each. Somehow they managed to have a connection to every terminal yet it all tied into one run of cable going to the amplifier. It appeared that both of the stereo wires were connected, but seemingly did nothing and the other would power both speakers. I have the nest of wires in my truck and I plan to see if I can reverse engineer the mess. Based on how much we were struggling with the overall volume (given the nominal 8 ohm speakers) and the horrible sound, I am guessing that they managed to wire them such that they had a 16 ohm plus load while being out of phase. To make things worse they had both wires in parallel at the amplifier on one of the two stereo channels. Part of what helped us identify the issue was trying to go to bridged mode and having the amplifier shut down clipping. It's a wonder that nothing was damaged since they have been hooked up this way for at least 10 years.

When we left, the overall sound had improved to the point that I was actually enjoying the music we were playing while adjusting the system. I even joked about Imax being installed.

It's genuinely pathetic how poorly the system was setup and that it took me/us this long to figure it out.

Does anybody have any idea what they wiring goal for the speakers may have been? I'm thinking they have have been trying to wire the highs together in series, the lows together in series and then the two in parallel, but I have no idea...

Have any of you ever had to clean up after a mess like this?