Bollocks - typed a huge post and MN went offline.
I stepped away from this thread yesterday as I was feeling crap enough after losing a mate, reading the 'hired killers' bollocks was enough to make me blow a gasket - so I withdrew.
I'm so glad to have come back today and read the more intelligent, reasoned and less antagonistic posts. Scaryteacher - excellent and measured as always 
Loopy - I just didnt explain myself properly. CEA is 90% of fees up to a maximum of £XXXX whichever is less - not (as assumed by the OP) 90% of all fees - if that was the case surely Eton would be full of mil kids.
The 'better' schools are nowhere near the £XXXX bracket, so the forces person has to top-up. Schools aimed at Military Children (like Duke of Yorks) are closer, but not considered as good. I have a number of personnel here that qualify and have children at Boarding Schools - every single one of them pays more than 10% - a couple way, way more.
I think your example of 4 children all boarding at 8 yrs is unrealistic and unlikely. For one, CEA is accounted for every year and every posting. It's not a 'right' and the forces person still has to qualify yearly. They dont just plonk their kids in boarding schools from 8 to 18 you know - and as most service personnel move on every 2-3 years they are unlikely to qualify at every posting.
Knittedbreast: you know whats expected of you and what life will be like and you made the choice to go into it If you think that do you also think it of someone who has a child if they are on benefits? I dont see the difference - they would also know what life will be like. Do you really think the children should suffer because of a decision by a parent? I think that is a terrible attitude.
OP: Now that you have qualified your 'friends' circumstances (lets be honest here, she's not really a friend is she - does she know what you think of her?) I would applaud her actually for looking ahead. There are only 2 SCE Secondary Schools in Cyprus and one is not good at present - lots of problems. I certainly would not send DD there. Maybe she has been informed of this and has decided to do the best for her DC's education, and that best is not sending them to a bad school when there is a better option. This school will hopefully be able to turn it around, and then DC can join their parents. I too am surprised at your ignorance of the situation considering your military past.