Nonsense! Many have done so and succeeded. Why would one have to be mental to do it?
Practical advantages - a wonderful new life, a new start, a new situation - what could be more practical than that?!
You can avoid this hassle by postponing your registration (and declared date of arrival) until you actually find work, if your contract is permanent or for at least 1 year you can bypass the tiresome temporary L-permit altogether and be awarded a B-permit. You don't need any permit to stay at someone's place, to stay in a hotel, to rent an apartment, to look for a job etc.!!
The official figure to live off may be something like Fr.100.-- per day, but you can get by on much less if you are careful.
I moved here alone (initially to Ticino) and with no permit, no employment (in Switzerland), I lived off savings and a part time job in a bordering country (Italy). My living costs were lower than those mentioned by others, rented flat Fr.750.-- per month (including heating etc.) in a town close to the border.
For as long as you have no permit you don't need to pay health insurance here. The insurance company will start it off for you from the date of entry marked on your permit (not before, whilst you are still job-hunting and haven't registered, - I only registered well over a year after being here to save (a lot of) money and hassle).
When I did register, I no longer worked in the bordering country and was simply living off savings. To gain a B-permit I declared myself as self-employed and taught English part time privately (with fluent Italian which is a must) whilst looking for a job. When I found a job my permit category was changed from self-employed to employed and because the contract was permanent it was also converted to a 5-year one!
I was let go by the employer during the trail period (4 weeks), literally the day before the permit actually arrived, nevertheless that 5-year B-permit remained valid as reported the correct circumstances at the time of application thus enabling me to remain in Switzerland permanently and nobody ever queried what I was doing here! A permit for employment also allows self-employment, so I continued teaching privately, living off savings and even found out I was eligible for monthly unemployment benefits by exporting the unemployment contributions from the previous country - a fairly simple procedure.
I haven't looked back since and after just 5 years converted to a C-permit as by then I was employed again, plus I had saved enough money to buy a flat which I have since moved into. Although now I no longer work.
Without languages in Switzerland, it would have been a completely different story for me, probably near-impossible (although it depends on what jobs you are prepared to take up). Languages here are a must at least at an upper-intermediate level if you are coming without any real job prospects/solid career background/connections here already (I had none of these).
Coming here (even as a runaway) with nothing, including no family and no friends, is a huge risk, but even coming here with a bit of money saved up is also a risk, as you might run out spending it all simply on living in one of the most expensive countries in the world, in my case though it was a big risk that most certainly paid off. This was my experience. I say go for it, whilst you still can!