Yes, the game glitched on me twice (badly), once in the GARM Facility in the Swiss Alps, and once on the last mission in London, shortly after I got the option to choose either stopping Marchenko or saving the VIPs. By "glitched" I mean the game kept creating alarms, without any obvious reasons (which might be either a bug or have been implemented on purpose). I did not leave bodies for enemies to find, nor was I seen by enemies or cameras, nor did I run through lasers. In fact, I avoided enemy contact whenever possible (more on that later). Strangely, both times I was perfectly out of sight of any enemies.
GARM Facility:
In the GARM Facility, I tried reloading previous saves about 10 times, as well as taking different routes, which didn’t work. The game kept creating an alarm mid-way between the first and the second part of the facility, a few seconds after I was contacted by Elias. It didn’t matter whether I went through the door or the pipe. I fixed the issue by reloading a save before opening the door to the GARM Facility, the first door in the area, which must be opened by hacking the panel. Opening that door triggers the cutscene with Viktor poisoning you. The second time, I did not skip the cutscene, and I entered the facility via the vent on the ground, not the door on the first floor – and it worked. I was not contacted by Elias, nor did the game trigger an alarm. Therefore,
Save your game before opening said door to the GARM Facility. Keep the save file until you left the GARM Facility without the game (or you) having triggered any alarms.
Important note: When doing a new run, all tutorials appear to be reset. That means you are going to get the alarm tutorial upon triggering your first alarm on a run, on the right side of the screen, which I noticed in the GARM Facility, when the game kept triggering the auto-alarm. Therefore, if you get the alarm tutorial, you know it’s your first alarm. If you reload a save upon getting an alarm, you're going to get the tutorial again if triggering another alarm.
*** According to WhiterValkyrie, the alarm in the GARM Facility can be avoided by contacting Alex Vega upon entering the area, not Jim Miller. If you don't happen to have a save before that part, I suggest trying to take out all enemies in the first part of the facility, which might prevent the alarm from being raised. Maybe someone can confirm whether that works or not.
The completion of secondary objectives is not required for this achievement, as confirmed by several gamers.
London:
In London, I got the alarm glitch literally minutes before the end, which made me pretty nervous. Upon deciding whether to go after Marchenko or save the guests from being poisoned, the game – again – triggered an alarm, apparently just for fun. It did not matter which option I chose. This time, however, I took out all enemies in the area (the remaining 10 out of 11) and disabled any alarm panels and cameras I could find. It worked. Therefore, these auto-alarms appear to be triggered by enemies using alarm panels. Keep that in mind.
These where the only incidents where the game glitched on me. If the game happens to create auto-alarms elsewhere on your run, the same tips apply.
General tips:
* Save regularly, while always keeping a save at around 30 to 60 minutes back. You have a total of 11 saves at your disposal, make use of them - especially considering the auto-alarm glitch.
* Go for this achievement on your "New Game+" run. Knowing the game, the missions and what to expect will make it much easier, not to mention still having your augmentations, items and ammo from the first run. Also, doing it on your second run will allow you to skip all side missions without having to worry about not gaining enough XP.
* Avoid enemy contact whenever possible, most efficiently done by using the Glass-Shield Cloaking augmentation. When using this aug, do not use Biocells just to refill your energy. Instead, get out of your enemies' sight and let your energy recharge itself. Only use your Biocells to refill your energy if you are about to run out of energy (while being cloaked) and cannot hide, or your total energy level is low enough to justify a refill.
* Avoiding enemy contact means avoiding takedowns. Takedowns drastically drain your maximum energy capacity, which can be much better spent cloaking yourself. You're going to have a hard time completing this run using cloaking AND takedowns. Furthermore and most importantly; by knocking enemies out, you run the risk of other enemies finding their bodies and triggering alarms.
* It appears your Biocell energy is recharged to full upon entering new territory, meaning upon arriving at and getting back from Golem City, GARM Facility and London. Therefore, don't use Biocells to refill your energy when you're about to take the plane with Elias.
* Personally, I suggest maxing out the following augmentations (in order of in-game listing): Social Enhancer, Hacking Capture, Hacking Stealth, Stealth Avatar, Smart Vision, Sarif Series 8 Energy Converter, Implanted Rebreather, Cybernetic Arm Prosthesis and Glass-Shield Cloaking. LiDAR Mark-Tracker, Icarus Landing and Cybernetic Leg Prosthesis are important too, but, in my opinion, don’t need to be fully upgraded for this run.
* I used the Social Enhancer aug to convince Talos Rucker. If you have upgraded the Icarus Landing system, you can jump down on the left side after leaving his office, bypassing almost all enemies in the area.
* Upon having to decide whether to go for Mission 11 or 12, I did the Bomb Maker mission, using the Social Enhancer aug to convince Allison.
* I took Viktor out using the Killswitch.
* If you are combining this run with the no-kill run, using the Killswitch on Viktor might void the Pacifist achievement, which I cannot confirm though, as I did separate runs and it's actually Viktor who pushes the button.
* Do not run away from hostile enemies or panicked civilians, which might lead to alarms being activated, without you noticing. If you panic civilians, they might inform the police. You never know if the game triggers an alarm without giving you the alarm tutorial, because you've already relocated and can't hear the alarm anymore.
* Enemies being suspicious or going into "searching" mode is okay, as long as you get clear of them before they turn hostile. If there's several hostile enemies and/or your radar turns red, I suggest reloading a save, just to play it safe.
This achievement might be glitched for some people. There have been reports of gamers not getting the Foxiest Of The Hounds achievement, even though they've had flawless runs and never got the alarm guide/tutorial. I'm 100% positive I didn't trigger any alarms (neither before nor after reloading a save) other than the above mentioned auto-alarms, which kept showing me the alarm tutorial. Thus, if those auto-alarms constitute alarms that would void the achievement, I can confirm that reloading saves after getting an alarm is fine.