Clearly there are still problematic IP out there, and its fun to hear about the horror stories. In our licensing business, and is almost all serious IP licensing companies, modification of the IP is prohibited by contract to avoid the kinds of problems that are described here. There is a difference between IP and Consulting-Ware. Such issues are the reason why the number of IP companies has dropped from over 900 in 2000 to just over 200 today. The market weeds out the bad actors.
Its also good that people are starting to understand that IP is not some kind of variant to the EDA business. The top IP companies in the market today ARM, MIPS, RAMBUS are not EDA companies. There's certainly a place for EDA to play in the IP market like Synopsys has so well discovered, but that business, with the exception of the sales channel, is orthogonal to the traditional tools business units. Semiconductor IP goes into hardware, which is by definition-- harder than software. :)