I did some combinatorics to see what the likelihood of the perfect draw is (guaranteed 4 Provinces in 10 turns).
If you open Masquerade x2, the perfect turn 3 draw is MCCCE, with CC as the next two cards. With this draw, you can pass E to your opponents' Masquerades (if relevant), have $5 after trashing with your Masquerade, and start turn 4 with MCCEE. This turn 4 hand cannot be made worse by opponents' Masquerades, you can topdeck Stash for your Masquerade draw, but must not draw your second Masquerade for the final card.
26.5% likelihood of drawing MCCCE turn 3
28.6% conditional likelihood of drawing CC with turn 3 Masquerade
83.3% conditional likelihood of drawing C on turn 4 Masquerade
6.3% combined likelihood
Not too likely. However, it is still possible to live the dream with some other hands if your opponent(s) cooperate with Masquerade passes (willingly or not). Here is the bare minimum essential draws to live the turn 10 dream:
53.0% likelihood of drawing exactly one Masquerade on turn 3
71.4% conditional likelihood of not drawing Masquerade with turn 3 Masquerade
83.3% conditional likelihood of drawing C on turn 4 Masquerade
31.6% combined likelihood
Not too shabby. Sometimes those draws will result in a Stash on turns 3 and 4 (probably not MCEEE on turn 3). But even if they don't, you'll have a good chance of keeping your Masquerades separated and starting your first Province buy on turn 8 or 9.
There isn't much that can beat 4 Provinces in 10 turns, so its probably worth opening double-Masquerade on a board with Stash for a chance to live the dream. Depending on the kingdom and your turn 3, you can pursue or abort the Stash plan at your discretion.