My perception of what is too big for EDC is likely anything that would be to strenuous to physically carry. However, as society deems one who walks around with something like a K60 strapped to their back as odd, strange, freakish, weird, outlandish,.... I don't do that, and have developed a refined sense of what is acceptable size for EDC.
So, with the whole "biggest I can carry" model completely ruled out, as I want to continue to "fit in" with society, I'm still left with several choices and often pondering the notion of just where does society draw the line for carrying around a big flashlight? After all, if my jacket is bulging and anyone asks what I have there, I will be forced to reveal that I carry around a giant flashlight. Thus the notion of simply shoving the K60 into my inner jacket pocket is then additionally wiped out.
Most popcan size lights tend to fall under this same logic. However, producing a popcan size light doesn't quite induce the same reaction of shock and disbelief as does the K60. It still is easily fair game to be deemed "quite odd" though. This brings me to single 26650 size lights. PERFECTION! This winter finds me at the movies, going to parties, walking in the park, helping out friends and family, all the while, little be-known to my social spheres and at a moments notice, I could spring forth with a mind numbing 2,000 lumens 600 meters throw Acebeam EC60.
Summertime prolly 1X 16340 is cool.