Here is a snippet taken from grdBase.Tooltip_Assign:

IF SET("TALK") = "ON"
  *
  *  the following line of code looks pretty bizarre,
  *  but in some scenarios VFP insists on evaluating
  *  properties set in the Properties Sheet even before
  *  the form.Load fires, which is where we SET TALK OFF
  *
  *  if SET STATUS BAR is ON, the talk output is evidently
  *  sent to the status bar, because you only see the
  *  talk output when SET STATUS BAR is OFF
  * 
  *  ...I consider this to be a VFP anomaly, which has
  *  been there for a long time...
  *
  *  see also 
  *    XXDTES("XXFW.VCX","bizarre","cmdBase","Enabled_Assign")
  *    XXDTES("XXFW.VCX","bizarre","txtBase","UIEnable")
  *
  SET TALK OFF
ENDIF

In all my years of doing VFP, I have never seen this behavior before now. This tells me that this toggling
of TALK ON and OFF is an environmental thing caused by someting in VMP, because it never happens in any other
application that I'v done.

The solution that I seem to have found, which is working, is to put SET TALK OFF as the first line of the
BeforeOpenTables method of each form.