Better! Not Perfect! - Infinite Power
One of the key things to remember when you are doing work. Is always look to make things better but not to make things perfect.
This will allow you to get to a result that scales much higher up. Think of it is terms of the 80/20 rule. The first 80% of the value comes from the first 20% of the work, the last 80% of the work only provides 20% of the value. If you focus on getting your 80% of value out and then improving upon that to the the next 80% of the value in 20% of the time you can have an exponential effect. The amount of time to go through and get perfect very rarely pays off.
This doesn't mean doing sloppy work and skipping proof reading but it does mean that when you are banging your head against something, make sure it is something worthwhile do to rather than worrying if it should be one or two spaces after a period.
As long as your work is clean and you have caught the majority of typos (it is always important to check your work and review for both small typos and for big errors in logic) take your time and focus on the issue that is going to make a big difference.
Say you need to get better mileage. You get the hug bang for your buck, switching from an old suburban to a honda fit. Once you have made the switch the small changes to make your fit more aerodynamic will not provide anywhere the gains that you got from the big switch, so stop focusing on the car and look for other big areas to save energy/money (switch from Oil heat to gas or Solar).
Making the big improvement on the biggest issues will dramatically increase your overall value and will allow you to make the most efficient improvements, and essentially give you the chance to get infinite improvement, while spending all your time focusing on a single thing will have you top out at 100% improvement and cost an infinite amount of time.
Focus on the change from zero to one.