Yes, it does work fine, and the load on the lashing is not high. The mast partner does its job as normal - the lashing simply holds the mast forward into the partner, and only has to overcome the aft pull from the mainsheet, as well as any inertia from pitching. The lashing around the mast does not need to be tight, and I did not use Spectra/Dyneema etc - it is simply a piece of 6mm Dacron double-braid.
There is nothing to stop you using a mast gate - this is just another option.
Ross Lillistone