To my eperience, for taking pictures in low light, whatever film you use, at whatever EI, measuring the essential parts of the scene is essential. For instance measure the faces and give +1 stop. Don't worry too much about drowned shadows. You aren't doing landscape photography, nobody is interested in what's in the shadows.
I'd suggest that it is important for each of us to test and understand where we want the tones to fall on our prints. Placing faces at +1 isn't always where I want them on a print and shadows aren't always unimportant in dark scenes. For example many/most times for darker scenes I'll actually shoot to place the major portion of a face at 0 or sometimes even at -1 on the negative.
My choice here is a matter of personal taste, experience, and judgement. I do this because I have learned that I don't normally want faces in dark scenes looking like they are lit by the mid-day sun, instead I generally want them to "fit" the scene, I want them to carry the mood.
Because I have tested the limits of my system and understand that I generally want faces to fall a bit darker than others might, my shutter speed choice for dark scenes can typically be faster or aperture smaller than others might be using and that can help me avoid changes to development. It has become really rare for me to need to push.
Another concept to keep in mind. I find it truly rare to get all the right tones in the right place on the negative for a perfect straight print. I understand that this is normal, that almost everybody's shot can benefit from a bit of tweaking with burn & dodge or bleaching or whatever. It is not terribly tough to adjust a face from 0 or -1 up a stop to +1 or 0 in the print and I'm happy to do it because it normally makes a big difference in the print.
The only way I have found to get reliable straight prints with all the tones exactly in the "right" place for a straight print is in studio work with a nice set of lighting tools.
. My point was about the compromises which you'll have to deal with when it comes to low light conditions and pushing. In low light photographs onlookers intuitively do not expect detail in the deep shadows. So the best strategy can be to concentrate exposure on the most important parts of the scene to get right, whatever that may be and don't make too much compromises with shutter speed as you can not check on location if you got a sufficiently sharp exposure. (Provided unsharp pictures with detail in deep shadows is not what you are after)
