I think they did it to make an affordable guitar more attractive. You could email them and ask. The three knob set up is quick and easy I guess, you don't have to look down to sort out what's what on the run.
The Decree is nice though, and with a pickup upgrade would probably be remarkable.
I have a Blackheart Little Giant head into a 4 X 12 and it is a decent amp. I really, however, find my Fender Super Champ XD to be awesome - twin 6L6 tubes and 16 great voices including a few essential but decent effects like reverb, delay, vibrato, and chorus and some combinations; at 15 tube power amp watts. It's not a line six or vox chromie type thing. What I'm really finding cool but not cheap is the Blackstar Club 40 that has twin EL34's for about 700US.
Just a design decision on the three knobs on the higher end models I guess. Fender does the three knobs a lot but has the occaisional four knob 2 + 2 configuration. It probably has a lot to do with marketing and the target demographic.
I really like my MK and the cherry burst flame is really beautiful. I got it to replace a Gibson faded SG that was stolen from me and I like the MK Custom better actually. The SG had a lot of sentimental value though, because even though I had it for less than a year, it spent its first days in a hospital bed with me for nine days and, along with the Vox AmpPlug "lead" headphone amp provided me with some post surgical relief while I was on, unfortunately, near non existant pain meds because the morphine pump was driving my blood pressure too low for safety. I was hurting and the SG helped out some. The sting of having it stolen is still with me. I also had a Fender Hwy 1 fat strat stolen in the same incident. I could use that strat right now for a project I'm planning. Insurance covered the guitars, but it was unpleasantly compounded by the fact I had to give my x wife that I was then separated from 600US because her name was listed first on the homeowners insurance policy, and she had to rip me off for some significant money or I wasn't going to get the check - it got sent to her with both our names on it. I'm divorced very profitably now and she is appropriately in my personal history. My new woman, by the way, is very supportive of my musical purchases and encourages me to get way higher quality stuff, which is more satisfying and has lead to fewer but more thought out purchases.
I think the Decree is a good guitar, without doubt - plus you seem to find it strikingly appealing, including the features.