Huge starter procedure

When I make starters that need 2 steps, I just boil and cool the second 1.035 gravity step and add it to the first without decanting the first. Do I need to consider the "beer" left over from the first step when calculating the gravity of the second addition? In other words, does the second step need to be a sweeter mix of DME to make sure the final overall big starter is 1.035 again?

I just make starter with the 1/2 cup of DME and 1/2 Quart of water ratio for a rule of thumb and get it started. I then make one with 1 cup of DME and 1 Quart of water. After the smaller one is going gangbusters, I will add it to the bigger one. Works for me every time.

I will also do this and then split it into 3 smaller ones when I do 3 five gallon batches of the beer.

yeah, I'm making one big one (4 gallon) to split between 2 different lagers. I make different size starters for almost every batch according to Mr.Malty. So, I use beersmith to calculate the second step (water to DME ratio). For this one, if I take into account the existing first step beer after adding the second 1.035 wort, the overall wort becomes 1.027. I know I'm nitpicking here...just curious what others do.