How much does this affect our cap situation and our ability to sign an impact player or two here? Not talking CP3/Dwight big, just a young piece for rebuilding or someone who could possibly extend the championship window another year.
First, you have think who that someone is, and the conclusion is that there is no-one available this year, so whether Garnett plays out his remaining year or retires doesn't make much difference.
Second, Shaq makes next to nothing, so his contract is, for all practical cap purposes, irrelevant.
Third, replacing Garnett with anyone who is not at least as good as Howard will means that the window has effectively slammed shut.
Welcome to the brave new world.