Into wind for run-ups?

[Chimbu chuckles]

Who said anything about taxiing against the brakes?

First flight of the day a full mag check and prop check while parked is not unreasonable...provided not parked on gravel and done efficiently...that means quickly...not cycling the props 3 or 4 time for no reason as an example...once is enough, twice is overkill unless the first was sticking. In a twin once through to feather at 1500 rpm is heaps...not sitting at 1700-2000 for several minutes while you check each mag and then cycle the prop to see an RPM drop and then reduce to 1500 rpm for the feather check. All you are doings is heating the engine up and learning not a lot.

Every other sector of the day does not require anything...where does it say you need to do a full runup before every flight?

Every subsequent flight of the day requires, at most, a quick dead mag check...even that you can do parked just before you shut down...not while taxiing out.

Pilots get in the habit of doing the full monty every sector because when they learned to fly they did it every flying lesson.

Even first flight of the day I do the checks 'on the run' but I slow down to a crawl on a long straight taxiway and then increase power the minimum amount required, say 1600 rpm, quick mag check and cycle the prop(s) once and then reduce power back to low idle. The aircraft doesn't have time to accelerate much so I don't wear out the brakes...and any forward movement reduces stone damage significantly. There is not a SINGLE stone chip on my Bonanza prop and there never has been.

You need to understand also that a mag check done at typical rpms around 1700 shows you NOTHING you wouldn't learn by doing the same check at 1000 rpm. If you want to test your ignition system thoroughly do it in cruise...select L and R and leave it sit for 20 seconds and listen. If everything is good it will run smoothly...if not you may have a magneto problem but more likely it is a plug problem..if you are blessed with an all cylinder monitor and know how to use it you will be able to decide which it is and direct the engineer at the end of the day. If you have a little plug fouling you will be as likely to detect it at 1000 rpm...but if you always taxi leaned you won't get plug fouling.