Imo it works like this; there are some unfortunates on ET who contribute little, total trading noobs who post one liners about nothing, some are bots, and then some who just enjoy a fight and communicate aggresively.
There are others who are intelligent, contribute and others who don't post frequently but at least put some effort into a thoughtful reply when they do.
Due to the fact there are probably scores of new post each day, placing someone on ignore is just a filter to weed out garbage.
There is also the problem, stupid nonsensical posts have a habit of making one reply which results in either a flame errupting, or probably just as bad, the stupid poster won't reply, ie, you have wasted your time trying to correct an idiot.
So, the ignore is good, it eliminates more posts about nothing.
As for missing the gist of a thread because of gaps..... forgetabout it, you are missing nothing.