A: What you describe is not a basketball play and a technical foul may be assessed but it may not be automatic. It really depends on what is happening in the judgement of the officials. If the player’s momentum carries him out of bounds, no infraction should occur. If the player deliberately goes out of bounds to gain an advantage, a technical foul may be called but, again, the officials need to use their judgement to determine if it was intentional and/or an advantage was gained. Per the rulebook:
36.1.2 Each team shall do its best to secure victory, but this must be done in the spirit of sportsmanship and fair play.
36.1.3 Any deliberate or repeated non-cooperation or non-compliance with the spirit and intent of this rule shall be considered as a technical foul.
36.1.4 The official may prevent technical fouls by giving warnings or even overlooking minor infractions which are obviously unintentional and have no direct effect upon the game, unless there is repetition of the same infraction after the warning.
So, the officials may warn and not automatically assess a technical foul.