I have a control horn question for the elevator on a profile, about 675 square, 66 oz.  Given a 1/2 inch thick elevator, 1/2" square LE, ribbed, not sheeted, solid block in the horn attachment area with a Standard wire “U” connector.  Will a dowel vertical through the blocks, with a vertical 1/8 wire or with a threaded 4-40 or 6-32 rod be sufficient for long term use.  These are used in RC, but the forces in CL are a bit more abrupt and may be higher.

OH BOY!! Show and tell! 

I've never trusted that set up.  Probably just fine, but I like the one in my picture.  It's also easier to make the control surfaces removable, which all of mine are.  The turnbuckle is a titanium piece for steering linkage on a car of some kind.  The guy at the hobby shop gave it to me.  It's too long to be practical in a full fuselage but works great here.

The dowel method may not be everyone's first choice for a variety of reasons.  The real question is about long term use in control line at a competitive level.  Not trying to convince anyone to use it, but wonder if is more prone to failure than the more standard type control horn.