How does decay affect matchmaking and/or rating?

From the description of the PvP Matchmaking Algorithm, it looks like decay is used to increase your ratings deviation. Am I right to assume that a greater decay will give you more mobility ratings-wise?EDIT: grammar :D

You will be placed in matches ignoring decay.

Examples.

If your rating is 1700 you will play 1700 games.

If your rating is 1700 - 700 max decay you will play 1700 games.

Decay only affects your visible rating and Leaderboard position. Effective rating is fixed.

Like @dagger dave.5201 said, your MatchMaking Rating; the rating responsible for determining who you get paired with and against; will be determined by that of your effective rating, or your actual undecayed rating.

So a plat who decays down to bronze is still going to be matched against plat players.

As others said, the decay in visible rating only affects your tier/badge and leader board position. Your real reasoning is still used for matchmaking and rating adjustments after matches.

Your rating volatility is affected by inactivity. Volatility is not visible to you. Volatility reflects how stable the rating algorithm believes your rating is. Less stable means your rating deviation - used to calculate rating gain and loss - is more likely to grow.