It's actually a simplification of the GUI in alot of ways. As Ptarth pointed out, if you look at it from the point of view of the "research Points" being generated, the scientists are still scaled with your science power. Its just in a cleaner fassion, since the game doesn't display research projects as "research points" needed and accumulated, but rather as months needed, having scientists take one month off the EFFECTIVE time needed (which is what's displayed in the dispatches) makes it easier to calculate how many scientists you need to buy to bring the projhect down to the number of actual months you need to spend.
Example: A project that has a base time requirement of 100 months. If you have no science multiplier (or rather a multiplier of 100% base time), then the project tkaes 100 months, or 100 goons to complete (or some combination of the two equalling 100). This is easy.
Now, let's assume you have a science multiplier of 2 (meaning each month you spend researching is worth 2 "base" months). Then you can complete the project in 50 months, or 50 goons (each with a value of 2 months), or any combination of the two equalling 50.
Here's where the simplification of the GUI comes in though.
One way to display the information would be to say "takes 100 man-months", then say "Each month spent by the Hydral is worth 2 man-months", and "Each goon spent is worth 2 man-months". Now you can do the math yourself and see that 100/2=50, so (Hydral Months+Number of Goons-or "Goon Months") must equal 50.
OR
The super good at math computer can do the math for you and just say "takes a total of 50 months" and then you just figure out how many of those you want to be goon months, and how many are Hydral months.
Much simpler.
So that's the change that was made.