It is true that the P47 is a high alt bird, but the M has excellent low alt performance as well, as long as it still has the WEP - never waste all of it on the climb, save it for combat! The M with the WEP can tackle any MA bird with reasonable odds, even at 5k.
Like I said. It can do it, its just a bit out of its element. Its like a high-alt 190, it can do the job, its just not the best up there.
An all out dive is an escape maneuver. It means giving up the fight. 5k is not a lot and if the 109 (assume K or G14) pilot has any clue, he will easily catch up to you on the deck and then force you to fight at even worse condition where you have no room for vertical maneuvers.
HIGHLY situational. If you're near your own base, the 109 probably won't want to drop to low alt an engage with a reduced E-advantage. Last thing he'll want to do is fight 2 or 3v1.
If you're near the enemy's base, its a bit irrelevent, since you shouldn't be ingressing at 5k in a jug, and if you're egressing you're doing so for a reason, and are probably out of options.
The 190 has almost no roll rate advantage over the P47 - numbers lie. When the roll rate is fast enough to challenge the reaction of the pilot, it does not matter any more. If you can do a 90 deg bank in 0.1, 0.01 or 0.001 seconds, it really does not matter, unless all you are trying to do is to beat the network update rate and appear to be micro-warping around on the other machine. Against 190s it is vital that you do not allow them to fix their aim and time the shot. You have to keep your orientation towards them changing, so they have to keep correcting. This means movement in all 3 axes. Example: roll left and go into a break turn, then follow with a loaded roll to the left till you are in a right hand turn (think half a barrel roll). From his point of view, you are moving is a curved line that is difficult to lead with the guns and that will force him to steepen his dive if he tries to. By this point the 190 will either take a wild shot and break off or be sucked into a rolling scissors, where you have a good chance to reverse him if he is not careful with his speed.
You miss what I'm saying. The 190's roll compared to the P-47's doesn't put the P-47 at any real disadvantage in direct combat. But the 190's high rate of roll, combined with its love of speed, makes their attacks harder to avoid, since they can follow most maneuvers.