yeah, what you've explained here, especially windows vs ranges is what i assumed was going on, but i wanted to keep the delving post simple, hence the example with ranges. i need to reread and digest the rest of your answers, but so far i think the only misconception i had was assuming that confirmability was also happening under the milestone. regarding threat model, i agree there is no material difference (that i can see) and the primary reason we dont skip this in core is because we have to delete the spent outputs to maintain a UTXO set