Does that paper account for loyalty issues among the Austrian army? It may not matter if they have the theoretical strength to stop the Germans. If the soldiers support the Anschluss, they might not fight.
"Contrary to assertions that the Austrian army had been subjected to National Socialist infiltration, lie the facts that only 5% of soldiers were members of the "National Socialist Soldier's Ring" and that an enormous percentage (30-50%) of generals and officers were dismissed following the Anschluss." In OTL, she notes, "The invading German forces met with no resistance, with the exception of an incident in Tirol, where unaware of previous orders to allow undisrupted passage, border guards refused entry to German police forces. This incident was ironically demonstrative of the reliability of Austrian forces to defend the border..."
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The politicians were another matter: "Jansa was not oblivious to the National Socialist infiltration in Austria and distrusted many of the politicians. Thus, he chose to keep his plans as secretive as possible. In fact, he noted that not even Schuschnigg was informed of all his actions..."
Nevertheless to put the paper in perspective, what it says is that Jansa's plans (which were the product of years of planning, unlike Hitler's makeshift invasion plan) would have allowed Austria to "defend Austria's borders for a minimum of two or three days." Granted that Hitler much preferred a "no resistance at all" scenario, would that have been enough to deter him, or to induce Mussolini to intervene? True, Mussolini still did not want a common German-Italian border, much as his relations with Hitler had improved since the days of the Stresa Front. But so much had happened since then--both in terms of German rearmament and with regard to Spain, Ethiopia, etc.--that I doubt he would be willing to risk his relations with Hitler over a small country which was obviously deeply divided on whether to resist Germany (even if its army was loyal).