Just for fun I took a song I liked and chopped it up into two-measure (8 beat) clips.

Due to timing drifts, I stretched some of these clips (with Ctrl-drag) to get them lined up to bars on the grid (only slightly...6% or so, typically).  When I loop them via transport controls, the clips sound perfect.

But when I try and make them into groove-clip loops, the command to do so is greyed out.

If I double-click, they will appear in the Loop Construction view, but all parameters are greyed out.  (And I see in the background, a dark outline of the entire audio file--just the selected loop is highlighted and fully visible).

I don't get it--these slightly-stretched loops still have transients.  Why aren't they "loopable"?

**AND THE ANSWER IS**

I decided to post this anyway, even after I figured it out in the middle of writing it--in case it's helpful to someone else.  The step I was missing was that after the stretching I was doing, I needed to Bounce to Clip.  Then they are Loopable.

LOL The amount of times I find an answer half way through writing a post - and yes too right - no harm in documentation - posts don't have to always be questions... Cheers

For the record, in X1 (not sure about X2 yet), there was one project I had where in a particular track for some reason, regular midi clips refused to groove clip, even when I bounced them and what not. Never did solve that one!