Source support and preparation memory

The value assigned to $H$ at $0$ does not affect its associated distribution. The product $H{J}_3$ above is justified by the smooth evaluated source. No product of $H$ with an arbitrary source kernel is declared. General distribution products require a justified construction; smooth multiplication and singular multiplication must not be conflated BDH.

The comparison with $H{J}_3$ does not introduce a sharp variational model or assert a sharp-width limit.