pr00ne, as Napoleon found out in Russia, for every person deployed, you need the logistics chain to support him/her.
Absolutely! I recall reading about Montgomery hosting a Churchill visit to the Eighth Army in 1942. Churchill was ranting and raving about paying 100,000 troops of which the minority were available for action. I don't think Monty bothered to explain and just let the great man rant on.
Those 5% have to come home. If you make it twice a year, that is 10% OOA in one year. 4 month tours and it goes up to 15%. There's training time, leave and the myriad garrison duties that require attention. And that is just for formed unit personnel. I don't have a figure to hand for the % of formed unit personnel but I bet a large sum that it is less than 50%. So the 5% increases to 10% for an annual rotation, 20% for a six-month rotation and to 30% for a 4 month rotation.
The supposed Army between-tour length is 24 months and it was reduced to 6 months for the Black Watch and other units. No Army unit has met the 24-month target.
There was a figure for the % of Army deployed on Telic 1 and I think it was around the 40% mark. I will find out.