From your description it sounds like you are getting a good feel for what's going on in your system.Brief update for the thread readers/contributors. More details to come. Things have turned around considerably. I made a concerted effort to go back and chart as much relevant data as possible (thanks to apex). Was able to map out my PO4 dosing as well as water change schedule. With PO4 there were erratic results as I was learning my tank’s consumption. Once I dialed it in and dosed the same amount each day to give me a stable and healthy (yet in range) level of PO4, things stabilized. For me, this was 1ml daily split into am and pm doses of .5ml. This gives me about .02 ppm PO4 at any given time. In addition, I noticed troubling trends with my water change schedule. Won’t bore anyone with the numbers. Truth be told I’ve always changed the water out regularly but I did change my regimen from 5gal weekly to 15gal every 12-13 days or so. Noticed that my monti issue coincided with GFO increase AND the longest time in between water changes (which was about 24 days). So, I did a massive water change, and have gone back to a very regular schedule.
This has caused a massive turn around. To my utter shock (despite my local LFS owner claiming it could happen), my monti has exploded back to life. This is after being bone white and then covered in algae. Now it’s not all the way back by any means. Still plenty of algae. However 15% of the surface is as bright as it ever was.
With regards to the polyp bailout on the hammer/torch. This has stopped. The hammer took the brunt of it. Slowly but surely heads that were adjacent to the affected heads also started to bail. Couldn’t stop it even once I’d started dosing predictably. Finally I dragged the piece to separate affected polyps from healthy. Since doing this nothing more has been affected. Almost as if polyp bailout is an infection of sorts that works its way through a colony. However my torch (which had one branch die to bailout) was NOT fragged. It had grown too far into a rock making it impossible to take out. It has yet to have another affected polyp. So that throws a wrench in my bacteria theory.
Anyway, I’m cautiously pleased with the progress. I know it seems simple (dealing with low nutrients) and maybe it really is. However knowing your tank obviously takes time and you don’t always get the intended consequences. Time will tell if I’m on the right track but at the moment things are looking much much better.
The cause and effect: developing a sense of the time it takes between a change in water chemistry and when it's effect can be seen visually on the coral is probably the most important skill. Not changing other conditions (and thus introducing more variables) while trying to "correct" what you think is happening will help develop that ability much faster. For example, doing water changes on a set schedule will get rid of a potential variable and provide you with a more accurate idea of what is actually going on.
The rate at which things happen in reef tanks takes time to get a good feel for, having good data and good reef keeping practices will help speed that along.
On another note: You are reporting that your coral are dying due to "polyp bailout". Think of it in terms of your water chemistry. Polyp bailout is the symptom not the problem. The coral are stressed because of the water chemistry. Once the water is dialed in you will greatly minimize these problematic ailments the coral can suffer.