Lorax

Dr porsche: 12 point bolt and it was the ones on the wheel side, where a pair of vicegrips wont reach. The others you can usually find a way to do it without wasting a perfectly good socket.

Diego

Yeah, I had this problem when I had to replace the trans axle seals. I asked the Porsche dealer about it and they said to just drill the head off the bolt. I had a few that stripped out. I drilled the heads off and no problem. Seems that once the pressure is off the bolt the stud is only finger tight. These bolts are very hard though, tough to drill if you don't have good drill bits. I also tried the vicegrips and NO WAY the bolts are so hard that the vicegrips just will not bite into the bolt head and keep slippng off no matter how tight you try to make it.

Zero10

As long as there is no loctite on the bolt, you can just drill the head off. If somebody has used loctite, you can be in trouble if they strip.
Other than that, I would normally just pound a larger torx bit into the head, and use an impact gun or similar to remove the bolt.

1 hour is just about right. I changed both CV shafts in my 951, with just a floor jack and half of a set of tools. I had to use a 1/2" drive wrench, and a 1/2" - 3/8" reducer, making it really hard for the triple square bit to go straight into the bolts. While under the car I had to wedge my leg under the wheel to hold it still to get enough torque on the bolts while laying in the grass with ants crawling all over me. It only took me 1 hour and 15 minutes, but I took a break to get something to drink, and to clean up the old dog bone washers since my new shafts did not come with them.

Then again, perhaps the ants were more of a motivation than a hinderance?
Not to mention I've done ~20 CV shafts so far, so I have a little bit of practice.

bart1

Spray the with Kroil the day before starting this project. Worked for me!