The Sengpielaudio Visualization is fun to play with. I wanted to be able to compare a bunch of configurations for cardioid mics on the same sheet, so I drew a few up in a drafting program. See attached PDF. I modeled my Busman BSC1 mics and used them in the drawings for reference.
By studying the diagrams you can get a feel for how time delay and intensity are traded to vary the recording angle. By comparing the four configurations at the bottom of the sheet (the angle between the mics is a constant 90 degrees), you can see that increasing the distance between mics (increasing inter-channel time delay) causes the recording angle to decrease. By comparing ORTF and DINa (the distance between the mics is a constant 17cm), you can see that decreasing the angle between the mics (decreasing inter-channel level differences) causes the recording angle to increase.
To increase the recording angle - move the mics closer together and/or decrease the angle between them
To decrease the recording angle - move the mics further apart and/or increase the angle between them
The Shure and Schoeps guides, with diagrams similar to this, don't include DIN or DINa.
It is nice to see most of the common cardioid configurations tapers use on one sheet.
At Gutbucket: Doesn't Williams call his contraption the "crocodile"? I can see why...
-MIQ