Hello, I would like to ask for any tips/pointers in the process behind finding cheap premium fares/routes. I'm not asking for a specific route/fare, which I guess are a well guarded secret

but rather, how does one go about finding them. I know that there is a thread here (2013 premium fares), but I'd like to know how to search for these myself.
In particular, I'm interested in is the process behind finding a cheap premium fare using specific rounting. For example, on FlightFox the
"super cheap first class challange" the winner found LH FRA-DEL for $690.
Now, I'm pretty sure that was not advertised on any web or any newsletter, but rather the user found a 1st class fare with specific rule which allowed for some "fancy" routing to get the longhaul flight included. Thus my question is how do you find fare with such routing potential with KVS Availability for example, i.e. what fare rule/basis to look at, whether it is add ons, stopovers, end-to-end etc.
So, my questions are:
(1) How would I go about finding such a fare?
- do I "spam" ITA Matrix with numerous from/to options
- do I just look at first/business airfares with the KVS Availability Tool for many different
(2) Is there any chance of finding the really best outrageous deals without an access to GDS? ITA Matrix, KVS Availability tool, etc.
(3) Does a strategy for such search exist? Or is it just about brute forcing ITA Matrix with numerous route options?
(4) If I stumble upon a good first/business fare for A-B route. How would I go about finding out which routes I could try to combine it, e.g. C-A-B, or A-B-C, or C-A-B-D to keep the price as minimum (do I look at, add-ons, end-on-end, etc) i.e. what do I need to know about fare rules
(5) ... or is the secret really just to keep a long list of know cheap premium routes and then combine the fares (how?) to get from point A to B throug C, D, E etc. even if that involves changing airport and/or extreme flexibility
Thank you
p.s. my apologies if this isn't the best suited forum section for this question, I'm fairly new here and this is section seemed the best to me.