I would also go that route. The regulator is going to draw some power even in shut-down mode. Normally not a big deal if you use your PV daily, but if you leave one laying around, it could drain the cell. Not a problem for a protected cell, but could damage an unprotected cell.
Unless you need to power other electronics, it's always best to enable and disable power at the battery. Even with other electronics, I use a solid state switch to enable and disable power to the dc-dc converter. The converter never runs in shut-down mode.