In my opinion, they're not idiomatic, because of a lack of parallel structure (or parallel meaning). "This year's" and "last years" refer to different categories of things. (this year's reunion / last year's reunion) (this year's shirt / last year's shirt) You can't assume that "the shirt he wore in" will be carried forward.
New words, one handy idiom, and a 2-minute quiz — delivered to your inbox to keep your streak alive.