charley - it's not typically 2 weeks - it's usually 2-3 of days of feeling ill followed by a few extra days for the spots to dry up so they aren't contagious. That is the usual course of the disease for the vast majority of children. I understand that it is not nice to see your child unwell with anything - that does not mean that I would rush out and get a vaccine against it without thinking through the potential consequences.
Re effectiveness and duration:
"From the second to eighth year after vaccination, the vaccine effectiveness remained stable at 81 to 86%."
So we only know that it is 81-86% effective for 8 years so far. So that would take most children into their early teens/adulthood depending on when they get it - not so great if it starts to wane then when complications are more likely and they are usually more serious. (As has already been discussed on the thread)
What exactly looks good to you?
"It is not known how long a vaccinated person is protected against varicella." ?
or are you looking at the 10-20 years (bit of a gap there - when should you get a booster?) and skipping over the part where it says:
"But, these studies were done before the vaccine was widely used and when infection with wild-type varicella was still very common."
I'm not sure what you mean by a 'tiny dose' of a vaccine - a vaccine is a vaccine. They all carry risks. Just have people have been saying that you don't know how likely your child is to react badly to CP, you don't know how likely they are to react badly to the vaccine either. According to the NHS link - the risk of a serious complication from the vaccine (e.g.. anaphylaxis) is less than 1 in 100,000. I believe I quoted the risk of serious complications from CP earlier as being 0.3 in 100,000. The risk of less serious complications from the vaccine such as developing a rash are 1 in 10. Having CP is also more effective at providing lifelong protection (over 90%) without having to worry about when it will wane (with a range of 10 years!).