If you think there is a decent chance that you might have to move during the year, it might be worth talking to the landlord now, and ask if you can sign maybe a 6 month lease, or 3 months, rather then a 12 month lease. Or heck, even ask to have that clause removed.
If landlords are having trouble keeping their units full, they might be willing to bargain up front, to win you as a tenant.
The landlord will be flexible if finding a new tenant is easier then going after you for the unpaid rent. If you move out during the winter or some other time when no one is looking for apartments (ex: April in a college town) then it may be easier to sue you. I wouldn’t expect to get any more protection then is given by local laws – but, if local laws give you an out with 30 or 60 days notice then that may be enough to suit your needs.
Practically speaking, IME, in big cities where there are always people looking for a decent place, I don’t know of anyone who’s had a tough time getting a new tenant to fill their space if sufficient notice was given.
In my case, I had to break lease quite suddenly. My landlady was a peach though, and she did try really hard to get someone in there, but it took her a month and a half to do so.
As someone who has been a renter all my adult life, that clause isn’t uncommon, but neither is it universal.
Also remember that a lease, being a contract, is negotiable. It is always easier to negotiate up front, before you sign, but even after you do sign you can always ask. So if, for example, you had to move you could ask if the landlord would accept 1 month rent (or something) or if someone else could take over the remainder of the lease, or some such. I don’t really encourage that, but sometimes stuff happens.
In particular, if at some point you become unable to pay the lease PLEASE contact the landlord BEFORE you fall behind! Sometimes (though not every time) landlords will accept a part of your rent in lieu of the full amount (though you may have to eventually pay him/her everything) or will simply not come after you if there’s no real chance of collecting though the latter is rare.
I once negotiated a 6 month lease from a landlord despite a stated policy of only 1 year leases by stating that, due to employment and college issues I could only guarantee six months rent - after which either I’d sign a standard 1 year lease or move out. The landlord agreed, and I got my six month lease. You may wish to try that yourself.