The documentation for this project is, at this moment, painfully incomplete and in order to update it it will be necessary to go through every source file and write Texinfo docs. That is a time-consuming and painfully daunting task, which is probably the reason the docs have been unmaintained for so long.
Another problem which plagues Blitz++ is the complete lack of comments throughout the code. That is a somewhat important barrier to entry to those that know a bit of C++ and have some interest contributing something to the library. This problem is easily fixed by adding more comments to the code.
So a easy way to sidestep both problems is to adopt a source code documentation generation tool and rely on it to generate the API's docs through the comments on the sourcecode. If Blitz++ adopts such a system then there will be an incentive to write comments and it will be very easy to generate perfectly up-to-date documentation, which is something this project desperately needs.
So, what about it?