Exactly, the NerdSEQ runs at 24ppqn internally which would mean 6 equal ticks per step. 4 step would usually be a full note (if you set the gate and/or change the note on the first step and stop it after the 4th step) if the groove is all set to 6. Half a note would be set on the first, reset after the 2nd etc.. Quarter note would be just on one step. Longer notes...just as you want, you can create the notelengths like you want to and they are no real limits. Shorter notes would indeed utilize either half gates or with the tables and there you could create even shorter notes/gates.
From what I understand, and based on that it seems reasonable to presume that 6 is the number of ticks for a 16th note (since 24ppqn is the standard clock for MIDI and the required external clock so that Nerdseq runs best), is it correct that in order to retain the 64 steps per pattern, the largest note value I can have in the patter is quarter note (at 24 ticks) ?
No the largest note value can be infinite.
If I needed larger notes (half notes, full notes), I'd have to "merge" a few steps into a larger note and thus "lose" the option to add 64 individual steps/events. Correct?
No, you just say on one step to change/start the note and on whatever other step you stop the note (which means stop the gate for CV/Gate tracks).
You don't lose anything. And in between you can manipulate this started (long) note in many ways on every step and even deeper within 1/6th step (using the tables) or dynamically (using the automators).
And generally speaking, a pattern is 64 x 16th notes, so it a Nerdseq pattern runs at 16/4 when no BRK is utilized (I'm not taking Tables into account here) and if the default Groove is at 6. Correct?
Yes 64 steps of 1/4 notes in the most basic way if groove is set to 6. Patternlengths can be changed as well as using BRK commands. And if you chain the patterns (= doing a simple arrangement in the sequencer screen) you can get much longer sequences. You can change your own default groove which is set then for new patterns.
Just trying to understand how the available values translate to common notation values. Speaking of tables, those allow for smaller division of the 16th note, so it's easy to add trills, tuplets, etc, but without utilizing those you can get 32nd notes and somewhere close to 64ths. Correct? Again, not talking about gates at all, just focusing on what steps on a single pattern do.
Yes, if the table is connected to the internal tick base, then you could get 1/6th of a quart note resolution. (And since you say notes...all of this applies also to any other functions/effects)
You can use the tables to create duplets or triplets or very odd stuff. You could much easier if talking about gates/triggers using the ratcheting functions which allows to get a ratchet of up to 8 for a step, also with some odd ratchets here. You could combine both....
What I want to say basically, the groove settings are indeed interresting if you want to create odd stuff, uneven patterns that are not only uneven by steps etc...but mainly and probably for most people keeping it at 6 is how it's being used. And all the functions together can give you much more possibilities (and might also add much more complexity, so it can get very difficult to understand whats happening).