Hi there! ^^"
So, I recently noticed that I don’t strictly follow the IM (Index, Middle) technique, I kind of use the index finger multiple times, when there’s a break in between, or I even tend to start a bassline with the middle finger if the line starts higher up on the fretboard and then continues lower.
What I basically want to ask: Do you really have to follow the IM technique that rigorously and strictly alter between index and middle finger?
I look forward to read your answers.
I can’t speak for others but I don’t. I mostly do what you’ve already described. Especially in a live playing situation.
This has come up before and both @JoshFossgreen and @Gio have said, as a beginner, this is your best bet. It’s a skill that makes everything easier down the road and I’ve found that to be true with my own playing.
Even if I start with using only one finger, when I get more comfortable with a song I find myself naturally playing with two.
As for Index then Middle, this isn’t always the case. Depending on the song, Josh has recommended starting with the middle. For example. Billie Jean.
Lastly, as you get more comfortable, the individual song will start to dictate whatever is the most comfortable way to play it and that can be whatever fingering works.
Well said @eric.kiser. I really focused on trying to use the fingering @JoshFossgreen recommended during the lessons. That has definitely paid off since. Once you have the basics down the song will pretty much dictate your fingering and you’ll find yourself adjusting automatically to the rhythm. Which is pretty much what you just said. 
Well, thanks, in that case I’ll keep it up and let the feeling flow! ^^"
Thank you for your answer, I really look up to answers from people with live experience. ;))
The way I look at this is, you should learn the fundamentals and the alternating plucking technique is definitely one of those. But you don’t need to feel like you will be a slave to it or anything; in fact very soon in the course you will learn a technique for plucking with one finger per string while playing octaves.
The bottom line is that for fast chugging you’re going to need to be able to alternate and if you don’t do so evenly it’s really easy to tell, it stands out. So it’s definitely worthwhile to get good at the technique.
Then of course you’ll find lots of times you eventually violate it in practice 
But it is still worthwhile to learn and become proficient at, just don’t stress over it.
Jack Bruce and James Jamerson both used their index finger pretty much exclusively, so you’re in good company.
Okay, then I’ll try to have an eye on it every now and then while practicing, thanks for your help! ^^
Well, in that case… xD
Thank you for your help. ^^"
I think some faster transitions, it can help to use a certain finger, as they are not equal. For slower stuff, it won’t matter much. Sometimes my fingers just do what they want in any case.
However, having fun is more important than using the perfect finger choice, in my opinion.
That’s an opinion I can get behind!
Thanks for your answer. ^^