| Hi Chris,
I've not much useful to say except I had the identical experience.
'02 998
Bike connected to optimiser whenever in the garage.
Never had any battery trouble.
Vanned it down to Nogaro in France a couple of weeks ago for a trackday.
Battery totally flat when I unloaded the bike.
Handy tip #287 - When jumping the bike from a diesel van for the third time to go out for a session, do not get all giddy and put the jumpers on the wrong terminals. The resulting spray of acid from the tiny vent hole will go all over your bike.
Spinoli
Optimisers - hmmmm......
Solution - new battery from French race team.
Spnioli | 
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