Is that your impression of Socrates?
Anywho, the reasoning is due to the obvious issues with the accuracy of Stalinist accounts on show trials, Trotsky, the purges, Lenin, etc.
Stalin was a very deceptive person, who did everything he could to discredit Trotsky. From giving Trotsky the wrong date for Lenin's funeral to doctoring photos of Stalin with people he purged to ordering the director of the film "October" to portray Trotsky as a dithering and weak man, and to portray Stalin as the one closest to Lenin (we know that Stalin dithered and was a no namer before the revolution and Trotsky and Lenin were the close ones).
So, to not take the Stalinist accounts of what happened with a grain of salt, is like reading a neo-nazis account off he third reich and crediting it as accurate.
Stalin was a megalomaniac, who surrounded himself with sycophants in the party and media.
ex: “O great Stalin, O leader of the peoples,
Thou who broughtest man to birth.
Thou who fructifiest the earth.
Thou who restorest the centuries,
Thou who makest bloom the spring,
Thou who makest vibrate the musical cords.
Thou, splendour of my spring,
O Thou, Sun reflected by millions of hearts ...”
(Pravda, August 28, 1936.)
I'll pm you some articles to read on the subject when I get home.