T-block staging entry validated for model fit. Imported from staging batch duell-thimm-t, source entry 2123.
Gelli cites the Vienna Tendler witness as 1820 under Lupscher and Gommel. The local record already represents the same Chatelain adaptation, so the Gelli year is preserved as a near-variant rather than forcing a reset of the current 1819 base year.
Gelli also cites this 1819 Leipzig Chatelain-derived fencing treatise under the cross-reference heading Thibauld, confirming that the local Lupscher/Gommel anchor represents the same bibliographical work.