I've been thinking about the same question.  My current plan is to make a bridle lashed to the inwale scuppers somewhere near the stern.  I don't think that would interfere with the tiller extension very much, but I would love to hear a more "seaman like" idea.  

Hooper 

First, I don't have a Skerry, but in all the pics on CLC's website, they show the lug sheeted mid-boom.  I don't see where this couldn't also be true for the gunter sloop rig.  This has the advantage of clearing the aft half of the boat with the falls that will sweep across the deck when tacking/jibing.  

In some pics, the block with a becket is attached mid-boom, leading the control higher and out of the way.  On other boats, the becket block is attached to the center thwart aft of the daggerboard.  It's easy to install pad eyes at both locations and experiment with which arrangement you prefer.

Remember that cleating the mainsheet on boats this size is unadvisable.  If I was going to attach a block to my center thwart, instead of having a pad eye on the top where it interferes with comfortable seating, I'd install it on the underside of the thwart and have a soft shackle connecting the block when reaved for sailing.

Bridles are great but remember there are trade offs for everything.  More to rig, more lines in the way, etc.  A bridle can also be uses as a sort of traveler if rigged that way, potentially de-powering the rig when needed.

On my Eastport Pram, I have the bridle between the two handle grip holes so it's completely out of my way when I have to flip my body weight for tacking/jibing.  I would think on the Skerry the bridle would need to in the vicinity of mid-boom which might put it in the way of the skipper.  With scuppered inwales though, you could easily move the bridle arrangement fore and aft to find a sweet spot if one exists.

Mid-boom sheeting has it's own trade-offs, decrease of mechanical advantage but less line to haul.  There's also the discussion of where the boom will break in a mid-boom vs. aft-boom sheeted position, but that's usually for larger boats that would then have to jury-rig something.

 Good thoughts, Captain.  Sounds like some experimentation is in order.  

Hooper