I will not do that again then but if you can strip your plug, i definitely can. Just checked and lost plenty out of the tank again after just 3 weeks.
On older British motorcycles some owners used to fit a stop tap at the oil tank outlet which was closed manually after the engine had been stopped. It works, of course, but the consequences of forgetting to open it don't bear thinking about.
There was also an anti-drain valve fitted to Norton Commandos and others which allegedly stopped the oil tank draining out. This was totally automatic and hence foolproof.
There may be a proprietary item available in the Harley Davidson aftermarket.
The other alternative is to start your engine more frequently.