Thanks Pottster. You might be right, it might be this way 'by design'. That doesn't mean it isn't a problem nor that it should be ignored.
I submit it's an issue and I want to see how others feel. (1 user, Brian, has already responded in the beta group where I accidentally posted this first)
Personally it's a problem - don't make me think. Further, it'll be a problem for new adopters/users. It's not that I/they couldn't learn - it's that MLO is supposed to make my life easier, not force me to remember a bunch or archaic shite. Thurs is the natural/universal and likely most oft thought of abbreviation for Thursday (followed by Th.) Not many ppl I know typically abbrev Thursday as thu. And in 2015 there really shouldn't be any reason not to parse all natural language forms of the day/date abbreviations.
That's my 2c.
I'd like to hear everyone else's.
thx.