Our software team has been doing a lot of R&D work to improve the performance of our product. Of course, the management team would like to know how long it's going to take to improve the performance, and how much improvement we'll get.
I'd like to know (1) if there's any suggested estimation technique when you're estimating the time developers will spend working on items such as performance improvements
Also, if possible, (2) what strategies are useful for estimating the amount of improvement you might be able to get with a given investment
Further background:
Our specific research is on improving application performance such as content load, the perceived speed of transitions within the application and other aspects of the user experience.
From the developers' standpoint, we don't know how much improvement we'll get until we make the improvements, and we don't know how long it will take to make the improvements until we dive deep and come up with all of the different ways we might speed things up.
I've read the basic literature about software estimation techniques (story points, function points, etc), so I don't need a primer on those. We do have at least a good start on gathering baseline performance metrics, and I don't need more info about basic metrics right now.