I think reading that kind of thing dumbs down the game and doesn't allow the players to develop their own style of play. Of course there are some natural counters to specific situations in qw.

But here i will discuss another aspect of qw 4on4.

Player selection:
Assuming you do not have the possibility to throw in Milton in your team, you will have to work with players that are not as complete. Keeping a clan alive and staying competitive, while still allowing many team-members to play requires some thought put into player selection for official games.

Some Player-types you usually encounter in mid-div qw.
The CSer: Hardly ever engages in SG-cess, focuses on trying to sneak an RL to the Armor area. If low on health rather hides for some minutes in a remote area of the map, then risk losing the weapon (dm3-SNG, e1m2-start etc). High-ping, low death count. Attacks from behind if at all.

The Cesser: Will take almost any fight with SG. Focuses on creating pressure on the enemy team. Settles with GL or SNG instead of waiting for high-tier weapons. Doesn't mind dieing. Low ping, good SG-aim and not dropping packs is the key attributes.

The Roamer: This guy will usually be running quads and is star-player of the team. He will push far into enemy controlled areas and rack up a lot of frags with RL. Usually drops a pack when killed.

The Defender: This role can be played by the skill wise worse player on the team. The task is to get a weapon and camp the most campable area of the map(dm3-RA, dm2-tele, e1m2-ya/mega).

Having 4 players of the same type will result in a disaster vs equally skilled opponents.

on dm3 and dm2 i would usually wanna field a team with 1-2CS, 1-2 Cess and 1 Roamer
on e1m2 i'd prefer 0-1 CS, 2-3 Cess, 1 Roamer,
If you have one lesser skilled player with you, he takes the role of defender, replacing a CS guy.

Learning the play styles of your teammates is as crucial as the next pent. Fielding 3 CSers will likely mean the opponent will control the armors. To many roamers and it will be a pack-fest. 4 Cessers and the opponents will build up a high RL-count etc..

By having individual skins on your teammates, observing who goes for weapons, who takes sg-fights, You will see learn their game pattern. Check the damage stats. High damage done in a lost game, might indicate a lot of sg usage. Etc..