The more you go lighter (or should that be the less you go lighter?) the more you can't go back to heavy.
I've been pretty exclusively running in Vibrams and X-Talons since the last of the snow. Went for a quicky this morning in my 285's which most would class as "racers" - they felt like two huge clumps of lead strapped to my slabs of meat.
Now, this is not a complaint. I love the 285's. Got me round 46.6 miles of the Beacons last year with almost no complaints and after being completely immersed on a number of occasions, a surprisingly low blister count too.
I've just come to the point where they actually are noticeably heavy.
Can't wait for the new shoes IIShould be soon now...?