Of course, HYOH. For me, the design point of this loop is to provide a way to take a long trail walk in the backcountry of the southern Sierras. It is specifically optimized to form one long wilderness trip for those who are interested in an uninterrupted backcountry hike. That said, here are three options for resupply.
1) Start the hike at Roads End as the loop is described. Exit the loop at the junction with the Kearsarge Pass Trail and hike east to Onion Valley trailhead, and hitch down to Independence. I suspect that would be a full day off the trail. That point is about mid-way.
2) If you draw a line along the Bubbs Creek Trail you'll form a figure eight out of this loop. You could just hike it as two short loops instead of one long loop. Start the hike at Roads End and hike to the eastern end of the Bubbs Creek Trail. This is very near the junction with the Kearsarge Pass Trail. Then go west down Bubbs creek to return to your car. Then proceed to take the other half of the hike.
3) if you started the hike at Onion Valley you could presumably arrange for a resupply when you pass Roads End in Kings Canyon. I'm not aware of any package-holding services in the park, but you could look into that option.
All of these options would change flow of the trip entirely. It is a long way to hike without resupply, at my pace 9 or 10 days. But for me that is the whole point! If you want to hike in 4-5 day chunks, there are plenty of other ways to visit the Sierra and I'm not sure this loop has any particular advantage over other options. Pete – I don't know you, but I'll go out on a limb and suggest an alternative to planning a resupply. Hike the loop in the clockwise direction. Bite the bullet and carry food for 9 or 10 days. Since you said you'd like to have the option of taking it easy at times, then do just that – hike at whatever pace suits you. If you end up averaging just 5 miles a day, then return to your car via Paradise Valley (Woods Creek Trail). If you make slightly faster pace, then return via Bubbs Creek Trail. If you make a little more mileage, then return Colby Pass and Cloud Canyon. And if you find that you are in the mood to walk 15 miles a day, then continue all the way south to the High Sierra Trail and return via Kaweah Gap and Roaring River route. You don't need to commit up front.
If you start at Roads End and hike counter-clockwise, then there's no straight-forward way to shorten the trip once you've passed Woods Creek Trail. By hiking in the clockwise direction you give yourself more flexibility later in the trip.
Bear information: http://www.nps.gov/seki/planyourvisit/bear_bc.htm
That page has a link to a map that shows areas where bear cans are currently required. WRT this route, it includes the JMT section between Pinchot Pass and Forester Pass.