I've been pondering the same modification ever since I bought my boat four years ago. As with your 27, the Cherubini H36 was designed for jib sheeting with snatch blocks on the toe rail. The pro/con list always comes down to "its not worth it" for the type of sailing I do:
- Due to other factors such as hull shape and keel depth, I doubt that my boat can ever be made to point like those J-boats that make it all the way out under the Golden Gate Bridge against wind and current on a straight course; while I need to tack while still inside the bay.
- As mentioned by Ed, I have experimented with adding a third line to the jib sheet clew so I can haul it closer to the center line; although with my shrouds located far out near the toe rail the jib/genoa can't be pulled in any further than rubbing against the shrouds. I do have a traveler, so I can adjust the flow through the slot. Maybe I can point a bit better by pulling in the sheet – but its not a slam dunk improvement. Those darn J-boats still were getting under the bridge while I had to tack my way out.
- There's the expense for a mod that might night not give much improvement. Two years ago, my dock neighbor parted out from standard jib tracks to high tech ones, professionally installed, that can be adjusted fore/aft under load from the cockpit. The boat has been out probably 5-10 times since then.
- I really like the look of clean and uncluttered side decks next to the cabin top.
- Holes would need to be drilled in the deck for the jib track mounting. The underside of the deck is covered by the interior liner. Access holes would need to be cut into the liner for backing plates or fender washers. A lot of work and unsightly on the inside.
As Ed commented, the designed toe rail and snatch-block setup works fine for me. In light winds, just letting out the sheet will slacken enough that the snatch block can safely be moved for or aft. In heavier winds, I need to adjust from the windward side before tacking. I'm always crouched down or on hands and knees and holding on firmly when moving out of the cockpit.
I have made some slight changes to the original toe rail design. I'll take some pictures when at my boat today and post later. The jib sheet now has a better lead angle to the winch and the line is not over the deck as much. And I don’t need to worry about losing the expensive-to-replace original snatch blocks either overboard, or to a thief if I don’t stow them away after each sail.