Re: A question on ECDSA signing (more efficient tx signing)?
I'm not sure that you can do what you described above. i.e. you can't just add a lot of private keys, sign a message and then add up the corresponding public keys and use this to check the signature (if that is what you meant) even if you are using EC point addition. I'll have to have a look when I'm more awake (sober) 
No problem. I am sure it can be done. It is used for deterministic wallets for example and it for verifiable secure vanity address generation. It is an interesting property of ECC keys. I just wanted to know if any crypto experts saw any potential reduction in security as I have limited knowledge in the field of ECC. Unless I was drunk I don't recall it even being covered in college.
You may be right about signing and verifying in the method you described. I will try some experiments with OpenSSL. My assumption would be that if both are possible that given n keys that n key additions plus one signature (or verification) would be faster than n signings (or verification).