The restrictions are pretty much useless. Restrictions didn't stop this Nigerian guy, passengers did. Restrictions didn't stop the shoe bomber, passengers did.
You may not have noticed it, but terrorists just come up with new tactics every time some new policy is implemented. Even if everyone is forced to travel naked, terrorists will just have bombs implanted subcutaneously. If everyone is forced to get a 24 hour medical exam before using a plane, terrorists will just go after bombs or trains.
Giving your 90 year old grandmother an anal probe every time she wants to board a plane does absolutely nothing to prevent terrorism. Its only use is to give the government and airlines the chance to say "we did everything we could" when shit does go wrong.
Two things that do help is getting good intel on radicals and having passengers be on the lookout. After 9/11, the latter isn't a problem, but the former... well, the Nigerian guy's own
parents already warned the US embassy about him.
But by all means, keep supporting asinine measures that have no effect whatsoever other than to send out the message that "something is being done".