Sure spacer cut is much better.
Regarding length of topout springs there are two storys:
a) I suggested to cut 10mm from topout where the spring is "dead" (see picture above). This does not affect topout spring action, just makes room spring and lets forks extend more as side effect. Spacer cut does not extend fork, easier solution.
b) On evallarta's picture there are some Racetech piston kit parts visible. That kit includes replacement topout springs with much less stroke. Long time ago I was at Racetech dealer and they tried to convince me installing this 300usd kit. Was not convinced and passed on it, because it does not change basic design, pison similar too and don't belive that you get much closer to good aftermarket cartridge, went with Ktech RDS instead. One thing they meantioned was that oem topout springs are too long (mid working section in picture) and for racing shorter ones (Racetechs) are needed and oem long topouts cause confusion with sag numbers. I personally think that for street or occasional trackday there is no difference.
Only thing I would investigate is if it's a good idea to remove few stack shims for you light weigth, but I'm not expert on this.
You are correct that cutting the spacer does not add more stroke length, but what it does do is keep the amount of installed preload the same. Adding more installed preload is going to make the forks feel even more harsh on initial movement.
Also cutting the Top out spring (TO spring) does change the overall length, but it's so marginal it wouldnt matter. To get the true overall length you would have to full extend the fork which compresses the TO spring and gives you the reading. I think what Carlos is seeing is the fork now sits differently in the stroke which gives the appearance of "growing".
Just a couple things to add, and for others to consider. When you cut a spring, whether a topout spring or a main spring, you change the rate of the spring. So if you were to cut the TO spring you would change the rate therefore change the "curve" of the main spring. As Carlos mentioned the Race Tech kit comes with different TO springs along with spacers. They do this to give you more stroke. While cutting the OEM TO spring is an option, you better be sure you know what you're doing and the affects it has on other things.
And last, Carlos and I are on the same page on the Race Tech BPF Gold Valve kit. For the money they aren't the best (and I'm a RT dealer so that should tell ya somethin). You're better off saving money and getting a full aftermarket cartridge kit.