hi ethan
I flew out of KSFO for many,many years.
Runway 01r/l has a blast fence to protect automobiles driving on a major highway (101). I'm sure you have seen it as it is painted orange and white.
there is a smallish sign that says: takeoff power point, to which the controller is refering. You should not use more than taxi thrust until reaching this point for a couple of reasons, mainly to reduce damage to the blast fence, and as jets have gotten bigger over the years, their engines can really whip things up.
So what atc wanted you to do was to taxi up to the POWER POINT (nothing to do with computers), and have your engines and your own self READY TO GO/TAKEOFF AS SOON as traffic passed through the intersection with runway 28r/l.
You must still await TAKEOFF CLEARANCE, but when ATC says CLEARED FOR TAKEOFF, he wants to you start your takeoff roll as soon as he says so, not leisurely taxi up and then add power.
SFO is really sort of a small airport for such a big metro area. The runways are too close together for simultaneous instrument approaches (ILS), so ATC has to work hard at stuffing 10 pounds of sugar into an 8 pound sack.
I looked on one chart and don't see the power point mark, so next time you go there, look around for a sign...it may be on the right, not the left also. I can't remember.
Fly Safe