Talking about the no sport side of TKD, what are the techs you use the most, I am talking about the technikes suitable for the streets not the tournaments.
Everry time I use a block I try to damage using my block as a strike too, for example blocking a punch I use my forearm bones to cause pain when impacting the hand,wrist or forarm of my oponent. Another tecnike I like to use is the low kick no matter for distract or lower the guard or as an opening for the following tech. I love to use my elbows as a striking tools and also like to use joint manipulation to inflict pain and or to put down the bad guy.
Talking about incoming kicks I use deviation instead of blocking them, the arm bones are not to strong to absorve a nasty kick for that matter I like to deviate or change the direction of the kick closing the gap beetwen me and the bad guy.
TKD has plenty of technikes that are better to use than the roundhouse kick.
Manny
From a SD perspective, it is good to take a look at one's training to discover it's strengths and weaknesses. Taking TKD as an example;
Range attack - typical arms length distance. TKD has numerous strikes and kicks to deal with a range attack. Some are better than others. Keeping in mind that during a physical altercation our blood pressure, pulse and respiration go up, often dramatically, it is important to realize that refined motor skills will likely be unusable. Gross motor skills are easier to learn, retainable in long term memory and have a higher % of success as opposed to more refined, acrobatic or fancy movements. Always keeping in mind that training in a Dojang environment (loose clothing, controlled environment, warmed up, stretched out etc) will differ from a typical realworld 'attack'. In such a case, you may be at the beach in shorts and flip-flops. You may be in a dress with high heels or tight jeans and sneakers. You may be in an elevator, between parked cars, sloping surface, on grass, in a hallway etc. Will your range defense serve you in such an environment? If not, you need to train for something that will serve you.
Grappling attack - Will your TKD allow you do defend yourself when a determined attacker is nose-to-nose with you? Some may say that they'd never allow someone to get that close. But that is easier said than done, particularly if there are multiple attackers. Is someone does get in on you, do you have TKD techniques designed to deal with the attack? I like to train someone to be able to fight inside of a phone booth, literally. At this range we're looking at elbows and knee spikes (CQ versions rather than the 'martial-arty' type). Does your TKD teach this? Will it allow you to go directly into a throw, choke or lock (if appropriate to the situation and necessary)?
Ground attack - Will your TKD allow you to fight if taken to the ground? I'm not talking MMA style ground-fighting, that is sport. I'm talking down-and-dirty-get-back-on-your-feet-right-now style ground fighting. Submissions are for sport. They waste valuable time in a real world altercation and allow all sorts of bad things to happen i.e. attacker has/gains a weapon or has friends that jump in while you're on the ground.
Control techniques - Does your TKD have control techniques? Not every altercation requires you to gouge an eye or blow out someone's knee. I often give the example of your drunk uncle Bob at the family BBQ getting stupid. Are you going to wade into him with Dim Mak death blows or does your TKD provide you with some control techniques for a semi-compliant individual that we don't really want to bleed all over grandma's homemade potato salad.
Does you TKD provide you with training in de-esculation? Avoidance, escape or evasion? Improvised weapons use? Cover and/or concealment? Training in street clothes in real world environments outside the Dojang?
If not, and your purpose for training is SD (or at least is a strong consideration in the overall training plan) perhaps you need to seek out some cross-training into something that does...