This article discusses simple arithmetics that will help you determine your overall clan division skill given by the division skill of your each player. Feel free to contribute more examples on this topic, since number of possible combinations is quite high.

Operation "+" means "is in team with".

Let me start with something easy enough.

Lesson 1
div5+div5+div5+div5 = div5

Excercise. Say the target skill of the following teams.
A) div4+div4+div4+div4 = ?
B) div3+div3+div3+div3 = ?
C) div2+div2+div2+div2 = ?

Solution:
A) 4, B) 3, C) 2

If you've passed Lesson 1, you are experienced anough to advance to next lesson. Congratulations.

Lesson 2

Now the things become a bit more tricky.

div1+div3+div3+div4 = div2-3
div1+div3+div4+div4 = div2-3
div2+div2+div3+div4 where two div2 players haven't played qw together for some weeks = div2-3

It was proven to me by series of practice matches after pickup messages on IRC in last two weeks, that 90% of ppl in div3,2 and 1 have serious problems with slightly advanced elementary division arithmetics! I'll leave this problem free for some other scientific research.
It might surprise you but for all the cases above, the subjects I've met in reality truly believed that the real answer is "div4" for all the examples! Unbelievable? Surprising? That's the reality in QW today!

Maybe someone could write a web-tool that could help clans compensate this common disorder in correct determination of overall team div?

How are divs "calculated"? I always wondered.

hopefully this get some sense into the div2 clans searching pracc vs div3-5 ?

You need a definition for what divx is.

A div1 quadrunner is also much more valueable to the team than a defensive div1 player.. Div1 is also the division with the biggest skill differences.

An example. Valla+3xdiv3 > Sassa+3xdiv2 even if both Valla and Sassa are div1!

In EQL we looked at player roster and pre-season prac results and their performance last season. Add a general "hunch" to that, and then we made a big ranking out of it, kinda like a seeding. I think this is the way it was done anyway. Maybe some other EQL admin can fill me in.

But what about 1on1 - 2on2 div0 players etc.. do u only calculate players in 4on4 quality or does their abilities in 1on1/2on2 count?

You missed one div, i think its fair to say that div1 can be divided to div0 and div1!