Comment 1 for bug 537254

Hello,

I agree with those remarks about the on_change that prevent from double unit system to be used properly as explained in the OpenERP book ("ham" example).

In general, there are wider issues than just this on_change issue with the double unit:
- no double unit consideration in purchases (but you probably need it too).
- no double unit stock monitoring

As a workaround, for some customers we developed an alternative module for 5.0.x:
https://code.launchpad.net/~akretion-team/+junk/product_second_uom
The specification is here: https://blueprints.launchpad.net/openobject-addons/+spec/stock-movements-in-2-measure-units

Actually we are not proud of what we did and that's why we don't communicate a ton about it, we think the right way is to fix OpenERP to be able to use a second unit, but we were afraid that wouldn't be possible to fix it properly in 5.0.x without introducing new regressions/API changes and we had more important issues with accounting so we didn't want Tiny to loose focus and that's why we kept quiet about it. Now, we agree, it would be cool to take advantage of the 5.2 release to finally make it work. There is something good eventually in our module, it's the second unit stock monitoring, it could be reused, eventually as a module or in the core if refactored.