K7 may have had some prominent Alpha engineers behind its design (in addition to existing AMD ones, including but not limited those who came from NexGen) but it is hardly an acquired design. The alleged similarity between K7 and Alpha 21264 is greatly exaggerated.
http://www.azillionmonkeys.com/qed/cpujihad.shtml
I could enumerate all the differences between the two but it'd be less work to list what they actually have in common.
AMD hired former DEC engineers, they didn't acquire a DEC design or patents or anything like that. If you're going to argue that AMD didn't develop K7 on the basis of hiring engineers that had a lot of experience at another company then you must be claiming that Intel only hires fresh college graduates...
If you want a good example of an x86 processor that was too much of a port of a RISC one with an x86 front end bolted on that would be K5, which used Am29000 - which was not at all a bad processor design and developed by AMD in-house.
http://en.wikipedia.org/wiki/AMD_Am29000
Emphasis on being for a time the most popular RISC CPUs on the market. I imagine they would have eventually realized that fitting a 4-wide x86 decoder to this was an incredible bottleneck.
You can tell yourself that AMD completely through out all of its 29k talent when they acquired NexGen and hired ex-DEC engineers but I don't buy that for a minute.