well as i said its just an opinion, but i've always treated modifiers in this way
when rolling for leadership, a double 6 always fails, when rolling for anything lower than a 2+, a roll of 1 always fails. and when rolling 2D6 for a 2+, a double 1 always fails.
and as i mentioned before, turn 5 is the only turn in which "reserves AUTOMATICALLY enter" ie the only turn in which they are given the overiding rule that allows them to ignore the reserve roll. the modifier is to the die and not to the turn number. so you still have to roll for reserves on turns 2, 3 and 4.
obviously your debate is whether a modifier can modify a dice to better than a 2+.
my answer is no, because thats always a chance of failure. your answer is yes, because the rules don't say it is so. on the face of it because the letter of the rules is so, you guys have it. but in the spirit of the game, i still think mine holds more ground, as its always assumed a roll of 1 is a failure (in nearly all wargames) - regardless that GW removed this overiding rule from its rulebook.
we'll just have to agree to respectively disagree