Obviously, if we are talking about taking on endgame fleets, then it's with full skills. Skill-less applies to 1v1 sim comparisons and similar tailored situations.
Getting a shot exactly every 10 sec is rare, but not necessary. About once every 16-17 seconds is good enough to use up all 20 with skilled character. Using up all 20 isn't the minimum required performance either, you contribute beyond your weight long before that point.
No, nearby ships won't ignore you. Doesn't mean they can actually do much. Afflictor is fast enough to dodge a most projectile fire at medium range, so mostly you need to be aware of burst beams, unusually fast projectiles/missiles, special systems, fast fighters,etc and most importantly death explosions.
Example of fleet fight:
Piloted Afflictor + Fleet vs Titan-x IBB. No actual fighters, but Titan-X missile spam is even more annoying to deal with, so I'd count it as suitable demo replacement. Also few extra annoying ships like Lynx (long range insta-hit system + phase cloak), and several other ships cloaks and time altering systems (once again, imo more dangerous than simple fighters).
My fleet had no good way to deal with Titan-X other than using Afflictor (endless missile spam just doesn't allow to vent and easily catches my AI ships even under Avoid order).
Didn't use up all 20 shots, but only because I had to deal with Titan-X + it's aftermath and wasted some time going for Lynxes (and then picking other targets instead). Against more typical fleet composition it wouldn't be a problem.
Didn't find good enemy fleets with fighters, so here are 2 fights Afflictor vs 4 carriers (just picked whatever had decently fast fighters in sim, same both times).
Skill-less: margins are thin, and I have to trade armor for effective attacks.
Skilled: fighters can't follow me fast enough, carriers are free pickings. Herding is when fighters follow me away from carrier, and then I return and kill carrier before they can follow.