For the last two weeks, I've been trying what plenty of you have recommended. Instead of shooting 3 arrow groups during practice I only take one arrow out.
My first cold shot has improved drastically and my form has improved. I never believed that having "back up" arrows would play into my shooting. I'm here to say it does, for me anyway.
This place really is full of great information.

I don't shoot groups either.

I was taught to hunt with single shot weapons. It makes you focus more on the task at hand. I try to shoot each shot as if it is my only shot, because it often is.

I also now just shoot 1 arrow at a time, no groups shooting for me.

The last several years, I mainly have shot  one arrow at a time. I get more exercise that way and it seems my concentration stays more on point,

I also believe that the muscles get more time to recover between each shot so stay fresher longer.Keeps you more focused longer.
Cheers KIM

I shoot one, and sometimes two, finding that it works better for me as well. Concentration seems to be better. In shooting groups, I tend to fling arrows as opposed to making controlled shots.

One thing that I've noticed is that I'm a VERY QUICK shot (inbetween shots). Most of the time I don't even give myself a 1 second break inbetween shots while shooting groups.

This can effect accuracy big time. When shooting one arrow (groups) I tend to be dead on the money 95% of the time out to 40 yards.

Heck even at the top level FITA field competitions they have like 2 minutes for 3 arrows I believe.

So taking a longer break in between shot's is something I'm working on.

Maybe try shooting one arrow, take a 30 second break and then shoot another one after the 30 second break if shooting groups.

That's what I'm going to start doing.

This helped me tremendously at picking that imaginary spot instead of shooting an arrow then shooting the next arrows at it.

Considering deer don't stand there and let you take multiple shots at them this is very useful    

I used to have trouble shooting groups years ago when I started out.... so I shot a lot of one arrow groups.
. later I could do both and it's no big deal.

It comes with gaining confidence and becoming very successful on your one Arrow groups ....sooner or later you'll be able to shoot groups and after that you won't be able to shoot groups... because you're tearing up arrows      :D

Plus your arrows will thank you for it!

I have been practicing using this technique lately. Except I have three targets in the yard and each one gets an arrow from a different spot. I learned this afternoon that it works, I went against my better judgement and robin hooded a brand new arrow at 20 yards. I didn't realize it was really a known way to practice until I heard Fred Eichler mention it in a podcast. Robin hoods were cool before they got expensive lol.

I think the one arrow method is particularly fun and useful when you're stumping. Pick a challenging target, take that one shot, then move on, hit or miss (hopefully a good miss).