Technique
As always there are various methods to skin a cat. While wing down/cross controlled works fine in a Cessna/Piper or similar, and various straight winged large planes, it has issues when applied to a swept wing aircraft.
Wing down can be flown by a competent pilot on most aircraft. On the A320/330/340 etc it is not the recommended method due to the interaction of the roll control laws. (AI test pilot comment on matter: "Why would you want to do that?" (in French accent).
The application of cross control on the swept wing jet, based on flight data, shows positive correlation with Euler angle instability in roll/pitch/yaw, randomised rudder inputs resulting in roll deviations, and variations in total drag, causing airspeed variation, requiring compensation in thrust, causing changing thrust/pitch couples and flight path instability from the trim change and speed stability for the off speed conditions. The most significant factor isolated in analysis if stability on approach was the activity of the rudder; the tracking task requires changes in the rudder angle, which results in a lag before roll occurs (which is a variable lag dependent on aoa amongst other issues). In almost 50% of the cases examined where cross control was applied, the aircraft resulted in a forward slip that was pilot induced due to excessive rudder application, and resulted in high lateral loads on the gear axles.
In comparison, an approach flown does into the flare in crab has effectively no crosswind issue to deal with until the decrab is initiated, which can be after the flare has been initiated and developed. The tracking task is simplified to roll control only to adjust the track to maintain the centreline, which is an everyday tracking task. Once in the flare, the nose can be accurately yawed to align to the centreline or runway QDM visually, using very large visual cues. The associated roll lags slightly and is offset by aileron as required.
2 cases may occur to confound the above; floating or wind change around the flare changing drift. In both cases the aircraft can either be landed with drift on, (all planes can do that) if required to maintain the lateral landing zone of the runway, or can have slight into wind roll applied to minimise downwind drift.
Horses for courses; every pilot I know is the worlds best, (with every fighter pilot being the best of the best of the best) so this doesn't apply to anyone other than.... me, naturally. Unfortunately, from a systems reliability view, we work with the lowest competency that is acceptable to the system on the worst day, which is obviously no one who is reading this post.
As far as this threads topic of tail skid adjustment is concerned, as has been mentioned previously the crosswind was hardly a big deal, so any issues that are apparent have little to do with crosswind. With respect, this is not the first tail strike of a geometry limited design; I have personally watched 4 in the last 30 years (none were Asian carriers) while waiting at the holding point. The neatest was a US carrier B757-200 where the APU touched down before the main gear on a calm day.
The majority of pod scrapes, and high lateral g landings I have had to look at in the past have been related to poorly conducted cross control approaches. This doesn't mean you cannot do it, it just intimates that occasionally it is not done very well.
As far as landing on a single wheel, while the CS25 requires a single wheel touchdown load analysis to be conducted by the manufacturer, 14 CFR Part 25 does not. Boeing however does assess the structural load as such. ( At least one other manufacturer didn't...)
Alteon (Boeing) generally teaches what the customer has requested, if it is within the discretionary bounds of operational technique.
Final thought: if you really wish to persist with crossing controls on a swept wing jet, for those who have spoilers incorporated for supplementary or primary roll control, have you thought of what your stall speed becomes when you are in unbalanced flight, with spoilers up on a single wing? I lost a friend in such a case, along with the whole crew when they unfortunately found the answer at 5000' agl.
Warm Springs, GA