Personally, I've worked for a few startups and each one seemed to have little to no formal process for every function. Being that they are startups, agility is obviously everything. However, I found that without formal processes (with flowcharts; the whole nine yards) the companies seemed to have a ton of chaos surrounding them. I found it somewhat ironic that managers would tout how impactful The Phoenix Project was but would actively fight any documenting processes because they feared it would make the company too much of an enterprise and not a startup. This is just my own anecdotal perception of the culture of a select number of startups... but it makes me wonder if there is a correlation between the success of a startup and how well they can define what each task is. To answer my own question:

1. About 10% of our processes were defined and documented

2. Most of the time however they were not enforces

3. I think, like most things in life, there is a healthy balance between the two extremes. I think major functions like deployments, SDLC, incident management, and project life-cycles, should be documented but the auxiliary things should have lots of freedom. I think that regardless of the amount of established processes, a startup should be able and willing to adjust them as soon as a better process is established.