TT UI behavior described by dmertz confirmed for H&B edition: deleting previously entered SbyS mode data releases lock on Forms mode data entry. TT UI defect here is not graphically indicating in Forms mode for a field the data entry interlock behavior with SbyS mode - TT Forms mode data entry just seems broken to the user. I use SbyS mode for tax estimation in early Q4 when most data are estimates anyway and details not important, then power-user Forms mode for year-end when all details do matter. One way for TT to indicate interlock in Forms mode within the existing UI concept of operations would be a pseudo-Data Source of "Step-by-step mode entered data" via right-click menu.
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