Well I really have to thank you for taking the trouble to look at this!
Of course your right about midi thru. I had confused the function of midi thru with midi out.
I modified the code with your suggestion...
case midi:
MIDI.sendRealTime(midi::Clock);
break;
And this made all the difference!
My loop pedal has an indication led for incoming clock and that's how i knew clock signals were always reaching it.
I do appreciate the help 