"Midi Latency" is very small, no more than a few milliseconds, and in the old days, when we used synths, there was about 20 MS "slop". -We used big Midi interfaces like the Opcode Studio 5- 16 times 16 midi channels. That helped allot. Emagic had their own high speed interface to deal with "midi" slop. But really, it's really not worth considering in my opinion.
Midi latency is inconsequential compared to audio latency (the time it takes audio to go through the "audio to digital and back to audio" conversions that happen when we use a DAW (Digital Audio Workstation). This is determined by our audio buffer sizes and the A/D/A converter. The A/D/A converter is usually 2 to 4 MS, and the latency produced by a 128 sample buffer is around 11 MS (I'm doing that one form memory, so it might be off a touch). Most people run their systems at 128 or 256 samples.
And then we can add the latency that happens when Automatic Delay Compensation(the time it takes the computer to do a process that is usually caused by a plug-in being used for EQ, or reverb, or.... The computer takes that time, and automatically delays your entire audio stream by the complete amount of latency being cause by this process. That's the real big and messy one that can happen with Logic. If you record with ADC on, and then quantize, your midi can be moved to the wrong place, or decide to try and fix it by turning it off after you have recorded a few passes with it on, then change your mind.
So.... basically it's a freaking mess. I recommend you 1) keep a smaller buffer when recording (either 128 or 256 samples), 2) Set your Automatic Delay compensation in Logic to "All" so Logic keeps everything in line, 3) Avoid using plug-ins that introduce a large amount of latency until mixing (Linear EQ or Multipressor for example, in fact I'd suggest avoiding any Apple presets, they tend to either use these latency causing settings, or use plugins that can add allot of CPU drain if too many are used, like space designer for example.).
Finally you can use the "low latency mode" button when recording to be assured that you are getting things to land in the place they were meant to every time.
I hope this makes some kind of sense, latency is a very confusing topic, due to the details and the number of ways and places it can come into play from.
BTW The lesson you posted too talked about midi, and today, using VI's, midi latency is pretty much non existent.