Again, public access is the key to guerilla growing.
Personally, I would not guerilla grow as it is too risky. I prefer my grows on my property where I have complete control.
Too many variables which could spell doom for the guerilla grower:
Thieves;
Coppers;
Do-gooders;
Deer;
Conducting your grow out in the open;
Traversing back and forth to access the grow operation; and
No security whatsoever.
Growing is a time-intensive activity. Guerilla growing requires too much time where the grow is completely out of our hands.
It would be interesting to see a statistic on the success of guerilla grows from seed to harvest.
I think a surprisingly high number of failures would be evident.
Public access is only key to the point of "you have to be able to access some dirt", after that, the less public, the better.
For example, city parks have public access. But you wouldn't want to grow in a city park, would you?
Guerilla grows are, logically, far more successful in spaces that aren't widely available to the public.
And most grow ops I've ever seen/read about getting busted are indoor. And if they are outdoor, it usually 20+ plants.
Guerilla growers growing 3 or 4 plants (or in my case, just the one) are rarely busted, and if they are, usually the crop is just taken, and the grower is left alone (unless the grower is stupid, and does stupid things to get busted).