1) Question #1 at ~17:00ff. still makes no sense! If blue tacked to starboard in such a way as to initially give yellow room to keep clear (i.e., no crash-tacking required), then yellow must duly keep clear by tacking away–and a failure to do so promptly, resulting in blue luffing or (crash-)tacking away results in a penalty to yellow. If on the other hand, blue tacked to starboard in such as away to to not initially give yellow room to keep clear (in a seamanlike way), then blue must take a penalty.

2) My prior second question (i.e., ~21:50ff.) on leeward-windward rights, and room to keep clear, may be summarized rather pithily by the question: how does blue force yellow to luff up hard (and quickly)? Or when does yellow have to luff up hard (& quickly)? In many professional races, a windward boat steers aggressively clear as soon as there's a leeward overlap, and may even turn instantly head-to-wind if another boat has gained a leeward 'hook' in the pre-start. As against this, the agonizingly slow, fractional, incremental means of changing course & leaving room, depicted here, seems to make it impossible for blue to sail her course downwind (if she's acquired a leeward overlap in this way, and must now head back promptly to a mark to the right of both boats), or for blue to sail her course upwind (including a pre-start luff).

Some clarification on these issues would be valuble.
Thx,