In none of the books I have read is ATo described as a hand to raise EP. SSHE warns specifically against raising this hand EP, and suggests folding the hand in all TAG scenarios, and warns about raising it in "typical" games. A raise is afforded ATo when it is in MP3/LP, but not if it follows two limps; in fact, it is suggested over calling two limps may be incorrect. Raising the hand is discussed in conjunction with blind theft. HEFAP warns against playing AJo in aggressive games, so obviously ATo is even more suspect. HEFAP also cautions players to discard Group 4 hands entirely in strong games: ATo is the last hand in that group sequence.

The stretch from T to A is as extreme as a "gutshot" is gonna get, So considering its "outs" preflop is very dubious, imho. And nowhere have I seen unsuited holdings tabulated for their "backdoor" flush capability. With 2suited holdings, your flush will come in 6% of the time. That's almost 20 to 1; for simplicity's sake, assuming the relationship is linear, you will see your 1 card holding flush at a 40 to 1 rate. 2-gap connectors will fill 1.4% (if my source is correct) of the time, that's > 95 to 1. I cannot tell you what the odds against filling a 3-gap holding is, but it's greater than 100 to 1, huh? Adding your "outs" in these two situations seems pretty sketchy. Moreover, Miller states explicitly that ATo plays much better with a T flop than an A flop pairing. The rationale is fairly obvious.

So, according to both Sklansky and Miller, ATo should NOT raise the blinds EP; nor does factoring in the "backdoor" capacity of this hand (we're talking pre-flop) obviate the warning whatsoever.

That said, thinking about the flop from a purely mathematical perspective, you have roughly 4.5 outs at best. However, the chance that catching an A is sufficient to win is compromised by the prefop raiser and his holdings, so the odds should computed to reflect that. Let's say you have 3.5 outs, being generous. You're getting 11 to 1 to see the turn. This is slightly negative expectation, since you need between 10.5 to 1 (4outs) and 14.5 to 1 (3 outs) to play correctly. There are no implied outs, as the bet doubles at the turn.

I think this is a fold on the flop. I think this is what Sklansky means when he says you want your opponent to make the mistakes, not you.