I am pretty sure that TAPR does not help any more than the other licenses with regard to patents. You only get rights to license patentable IP if you own the patent, therefore the provision of the TAPR are legally baseless. If the physical design is not covered by copyright, the license provisions are worthless.
TAPR is more based on contract law, but the drawback there is that someone can still patent the idea by deciding not to agree to the contract (simply reading the design cannot constitute agreement), and contracts can not be passed to third parties. If B enters a contract with A who creates the design, then C must also enter a contract with A. B cannot pass on contract rights to C. This really hampers open sharing.
Unless the law changes with regard to hardware IP, then there can never be a really effective open hardware license. I don't think it is a case of waiting for some really clever lawyers to find a loophole.
However, if hardware protection was as easy as copyright,
it would be a complete disaster. Already, companies are trying to "own" the product you buy, and prevent you using it in ways they don't approve (e.g. by using your own supply of coffee
http://www.theverge.com/2015/2/5/7986327/keurigs-attempt-to-drm-its-coffee-cups-totally-backfired). If everything you bought was licensed, then they could prevent people selling second hand on ebay. That would be a gift to people like Siglent, who currently use other underhand tactics to manipulate the market.
So unless a new law was really carefully worded to allow open source hardware without abuse by corporates, we should be very careful what we wish for.