Well, that method is very common for preserving aviation engines that cost a whole lot more than this one and I know people who do it with auto engines. Truth is few things work better. That said it's almost always done with the engine out, say in a crate or on a stand. I agree it's not a good idea with the engine installed due to the hassles and risks involved in bringing it back to service.
Sticking just with the engine the best way of preserving an installed one is done using the same method used for installed aircraft engines. It's called flyable storage and is good for at least 6 months. The procedure has been used by NASA, the military, ect, for decades. I've used it many times on cars as the needed items are readily available.
Basically it involves changing the oil (better to replace/mix it with Aeroshell 2F, which works as well in cars) and running the engine for 10 minutes. That's followed by fogging/spraying each cylinder through the plug holes with Aeroshell 2F, (or WD-40, LPS, ect) while turning the engine over with spark and fuel disabled, installing desiccant plugs in place of the spark plugs, closing all openings (intake, exhaust, PCV, ect) with humidity tape or bagged desiccant, and a few other minor procedures. Thereafter the crankshaft should not be rotated until the engine is brought out of storage.
At minimum change the oil *before* you put the engine to sleep and leave it alone after that. The worst thing you can do is periodically start, idle, or drive the engine a short distance. An engine (in storage or not) that is run without reaching full operating temperature plus 30 minutes will generate a lot of sulphuric acid in it's oil. Idling to operating temperature is insufficient and bad for other reasons. The rule is if you start it, drive it at least 45 minutes to one hour. If you can't do this leave it alone.