OK, here's what I think.
A trader's 'journal' should be an account by a trader of their trades, including the good and the bad trades, with charts if the charts help to illustrate what the trader was trying to achieve.
Cumulative P&L (expressed as percentage or actual Pounds/Euros/USD) and observations of what works and what doesn't work may be extremely useful to other traders. A journal should also include descriptions of common errors made by the trader, such as entering or exiting a trade too early/late.
I don't regard a list of posts suchs as 'long YM @ 16100' as constituting a trading 'journal', but that's just my opinion, maybe others think it does.