Is there any value to or halachic discussion about keeping the laws of shabbos during the week?
Were there ever Rebbes or great people who did this on any level? (Excluding those who do it as part of Tosefes Shabbos, like the Amshinover Rebbe)
I'm referring to someone who, say, decides to "keep" shabbos for 6 hours on Tuesday.
Is this discouraged or prohibited?
Or might there be value to this?
Please provide sources.