TCPAck does help with lowering your PING, it also takes MORE bandwidth creating a higher potential for bottlenecks if you are choked already. (Such as running 5 clients on a low bandwidth provider.)

All said and done PerzianPenguin appears to be posting 80-90% unsubstantiated crap and having people use tools that the average user really shouldn't be screwing with. You jack around in the registry without knowing exactly what you are doing and you can turn your hack attempt into a nice long reload of windows. GPEdit is exactly the same, you can screw things up so bad so fast. None of his advice is coming with a warning of "Hey you may brick your system if you do this wrong..." and it's all sensationalized in his presentation style.

Lose the caps lock.
Post some supporting evidence.
Warn people that these changes may have a negative impact.

Oh, and use the search function... The TCPAck hack has been discussed here at length already.