mrmb

Imagine a street-ridden bike with a 1000 gram tire up front and a 1000 gram tire in the rear.

Replace the rear tire with a 300 gram tire. I imagine the rider would notice a boost in efficiency.

Simple enough.

Now, put the 1000 gram tire back on the rear and install the 300 gram tire up front.

Is the rider going to feel like the 300 gram tire being up front provides the same boost in efficiency as it did when the 300 gram tire was on the rear wheel?

PS: For the hypothetical scenarios above, the "all else equal" rule applies.