Tool A, Will it fail? Maybe. Wood only moves in response to change in moisture content. So if your board remains in equilibrium with the environment it is in, it will stay fine. If not, the cross grain arrangement will cause the body of the board to either increase in size, width wise & brake the bond to the end part, or it will shrink and most likely cause itself to crack open. Hoadley's book "Understanding Wood" has information that will save you from making mistakes in designing your projects. The Federal agency "Forest Service Lab" also has publications to help you understand how to deal with wood changes. BTW, finishing will slow changes in moisture but not prevent them.