Most of the things that reach all the way into CTransaction::CTXOut::nValue should not be doing this. The methods that do this should not technically be directly interacting even with CTXOut, except for the ones that are in CTransaction.
Making nValue private will prevent more "bad" code from entering the client, and is the start of fixing this problem for good.
I have made a pull request but I think it was prematurely closed.
Reviewing/testing changes is our bottleneck.
There are two problems with "I'll just encapsulate this..." changes:
The last release was a "code cleanup" release, that would have been a good time to do this. Getting consensus on the names of accessor routines BEFORE submitting a pull would have been a good idea, too ("GetPresentValue"... bleuch).
Not wasting your time is why I only changed one thing in the commit to close off the problem before it gets any larger than it already is. I made it easy to review intentionally.
Present Value is the standard accepted term for the idea described by the variable "nValue."
http://en.wikipedia.org/wiki/Present_value
It's a very fundamental and basic term from finance and I had no idea this would be controversial.
I assumed you would appreciate me honestly expressing my current motivation rather than obscuring it and submitting patches without any explanation as to what I'm experimenting with.
Accessor methods are generally named "GetFoo/SetFoo", although it's not universally agreed that accessor methods and making every variable private is always the right thing to do. For a lightweight class like CTxOut, I don't see a lot of benefit to Get/Set methods.
RE: "expressing motivation" : I haven't said anything about the motivation for this change, I'm just explaining why little changes like this aren't welcomed with open arms.
RE: wasting time: arguing about little changes like this, exactly like we're doing now, is a big waste of time.
PS: you might look into building on top of Michael Gronager's libcoin, it is an extensively refactored version of the Satoshi codebase: https://github.com/ceptacle/libcoin e.g. https://github.com/ceptacle/libcoin/blob/master/include/coin/Transaction.h#L197
I can't vouch for it's security or stability, though.