The short answer to your question is yes, OO techniques can be used to build better engineering (i.e. numeric) codes.
The longer answer is that applying OO techniques have been adopted very slowly by the numeric computing community because there are some difficult problems in marrying the two that are still being actively researched.
A very good resource for OO numerical computing is here
Slashdot Mirror
You say: "Phil Jones, ex-head of CRU, admits no GW"
Yet in the article Phil Jones says:
"I'm 100% confident that the climate has warmed."
Apparently, the article doesn't support your initial statement.
In the U.S. about seven children per day are treated in emergency rooms for injuries caused by contact with an electrical socket.
More information here.
Perhaps those children just aren't "average" enough?
The short answer to your question is yes, OO techniques can be used to build better engineering (i.e. numeric) codes.
The longer answer is that applying OO techniques have been adopted very slowly by the numeric computing community because there are some difficult problems in marrying the two that are still being actively researched.
A very good resource for OO numerical computing is here