Does it ever go up in a nice steady gradient, with no bumps or dips? 

First, as @Greg Dickerson mentions, educate yourself.Decide what type of investment you want - passive or one where you play an active role (or where you fall on that gradient).Depending on the above, your path will vary a bit but start reviewing all the deals and PPMs you can.Review at least 50-60 deals before making your first investment.

Measurements are scaled across a colored gradient that are plotted out on the map.

CRIME: Use Trulia to find the crime gradient for the property you are looking for.

There are gradients in between.

But you're definitely right, prices between Bridgeport and Midway are a gradient, so as prices rise further east it pushes the prices our west higher.

Keep in mind that since property taxes and insurance are also going up, your cash flows would be influenced by the gradient of change in these two factorsApart from that, another potential risk (on top of what @Taylor Dasch mentioned) (assuming a cash-out refinance per your post) would be lower equity in the deal (depending on how much you pull out) and therefore, a higher possibility of being in the red if the market were to go south  

Credit utilization's affect on score is a gradient and not step tiered, meaning your score would likely go up if you dropped the utilization to 10%.  

I was following along nicely and then suddenly the information gradient turned exponential and I felt like a deer in the headlights, especially when he talked about "Call Options on Steroids".

In addition, he/she understands heat transfer, pressure gradients they relate to volume, capacity and air flow velocities, state transitions, voltage/amp/resistance as they relate to three-phase, series, paralleled systems, blah blah blah.