Agree with Marioh. The issue, in many (most?) cases, is probably on both sides. That is, this game could be designed better so that the spikes occur less frequently if at all.
Doug: just because (you think) you close all programs and all windows does not mean no programs are running on your computer. You can have dozens of processes running invisibly in the background, while no program window is open on the Windows taskbar. For example, the internal Explorer program on your machine (if you have Windows) is running constantly, and you can't normally switch it off; and it's been known to crash. Same goes for your antivirus software: it's active all the time. (Didn't, in fact, someone report in these forums that they later found out the meter lags on their machine were caused by Norton antivirus software performing some unannounced and normally invisible routines in the background?)
Guess I'm just a lucky guy having little issues with WGT on this 3-year-old notebook. In contrast, I can't play TWO on this machine at all; can't see the ball, nonsense camera views. I tested the local version of the TW game on this notebook, too; the same Pebble Beach holes that are unplayable for me in the online version, displayed perfectly for me in the local version of the game. I could always see the ball & all the camera views were correct, so that's some proof for me that the issue is on TWO makers' end. (Unity Web Player?)