philipjent, yup, you got it right. You can do it when you track. You can do it on mix. You can do both.

I will frequently track bass, with some limiting since guys are always thumping and popping those strings. I won't usually gate the bass drum when tracking but generally during mixing, even if I'm adding some limiting during tracking. I will add some limiting and/or compression before gating the bass drum along with plenty of equalization before and/or after dynamic processing, if required.

And don't forget some compression on the lead vocals to make it sit well in the mix with the bass drum and the bass. I just can't figure out why people want dynamic range on rock-and-roll vocals? Shouldn't happen.

Zero dynamic range = maximum loudness (turn to another station please)
Ms. Remy Ann David

does the sarcasm go before or after the EQ?

it goes sideways.