Mash Efficiency for 10 gallons

Ok I've been doing all grain for 3 years and never worried about my efficiency. Today i decided that I would see what it was. Now my 1st question. I know that I'm to take a reading after i sparge before I boil but since I do 10 gallon batchs and batch sparge how do you all take your readings. This is what I did today. Collected 5 gallons and took a small amount and put into a sauce pan. Colected another 2.5 gallons took small amount put it into sauce pan. Refilled my mash turn with water to get ready for second batch sparge. Started my kettle on 1st 7.5 gallons as I was waiting for 2nd batch sparge. after about 30 minutes I started collecting my run off again. Collected another 5 gallons once again took sample and added to sauce pan. Continued to collect the last of sparge and add small amount to sauce pan. So is there an eaiser way to get this reading? After doing this today I know why I never worried about it before. Beer still tasted great. Am I over thinking this?

Overthinking a little...

You dont have to take the gravity pre-boil, you can do it post boil just as well. Also, taking random samples from different runnings will not result in a gravity reading that is accurate.

#1. Why not complete the entire sparge and then take a sample from the kettle? Why take 2 samples from 2 separate runnings?

#2. You CAN do this post boil, which will be a better gauge of your brewhouse eff. instead of just the mash/lauter eff. Pre-boil this will not really be your brewhouse eff.

Thanks. I had read from palmer to take a pre boil reading to figure mash efficiency which is why I was taking small samples because of the fact that I always start my boil as soon as collect my 1st batch sparge. Plus have been thinking about getting brew software and fiqured I needed to start somewhere. Thanks Again

First off, I do not check my gravity preboil. That being said, the biggest advantage would be that you could adjust your bittering hop additions to maintain the same balance as you intended. For example, I made a pale ale recently and expected an efficiency around 75% so I added my hops based on my expected OG. I ended going quite a bit higher on my OG but didn't know it until I was preparing to pitch my yeast. As a result my BU:GU ratio came out a bit lower than I had planned, and this could have been avoided. I was fine with it, I now set my efficiency at 80% when formulating a recipe. If you always hit the same numbers then you have nothing to worry about, if not you might consider checking your gravity before the boil.