Actually your boss is right, page load time is one of the fundamentals of On Page SEO (this includes enabling compression, minifying CSS JS and HTML, reducing the number of redirects and browser's requests per page, leveraging browser caching and many more ...).
If anyone is interested back in 2010 Matt Cutts actually mentions this and continued mentioning that this measurement has a part in page's ranking.
With bad load time you are providing a bad users experience which results in site speed penalty. There are literally hundreds of resource materials on the internet that talk about this.
Now Xmencute regarding your requirement, unfortunately I'm not aware of any plug-in that would straightforwardly enable you this.
Nevertheless you can take a look at the following IIS extension which offers some optimization capabilities ("Search Engine Optimization Toolkit"):
http://www.iis.net/downloads/microsoft/search-engine-optimization-toolkit[
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Also as a side note, you could actually achieve these optimisations yourself by coding them out in your web application, for example here is how you can do Bundling and Minification:
http://www.asp.net/mvc/overview/performance/bundling-and-minification[
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