Reinhardt CAN be VERY fast >.>

This is more so on the theory crafting side but from my post before people seem to think is speed is impossible to save in a reasonable way so I took the task upon myself to easily show how you can get him pretty high with a BUDGET BUILD and a OPTIMAL BUILD both based around speed though "DARTING BLOW" won't be used due to its lack of overall usefulness for these builds.

Reinhardt's base stats are as shown with no banes/boons.
HP 38
Atk 32
Spd 23
Def 27
Res 25

As you notice there is nothing super fantastic so lets say he has a boon speed bane res I suppose.
HP 38
Atk 32
Spd 26
Def 27
Res 22

Add a life & death 3 or Fury 3
HP 38 38
Atk 37 35
Spd 31 29
Def 22 30
Res 17 25

Now lets add hone, likely placed on a unit like xander or such.
HP 38 38
Atk 43 41
Spd 37 35
Def 22 30
Res 17 25

Now we simply add 2 goads from more free units like camus and since we have 2 its possible a cecilia has one on or something of the likes. This would be a plus 8 in attack and speed.
HP 38 38
Atk 51 49
Spd 45 43
Def 22 30
Res 17 25

Now lets say we give the first set of numbers DIRE THUNDER and the second set Blarblade+ and we'll remove goad for one fortify to make sure he is getting the max Blarblade buff (NOTE: Blareblades extra damage will not be put into that stat line).
DIRE LD Fury
HP 38 38
Atk 60 58
Spd 40 38
Def 22 30
Res 17 25

BLADE LD Fury (Not counting Added Blade Damage)
HP 38 38
Atk 60 58
Spd 41 39
Def 28 36
Res 23 31

We can see for Blarblade+ fury seems more appealing of the 2 with likely wanting a speed seal while dire would want luna/bonfire with an attack OR speed seal

These builds actually put Reinhardt as the SECOND best bladetomb user with Cecilia having 2 more speed..... though I would say Olwen is the most consistent blarblade user at a close second (she is my Fav unit^^). As you can see reinhardt can reach pretty intense speeds through buffs such as any cav unit and this isn't counting merges or seals in the statline

for fun +10 Rein with listed builds before.
Dire L & D + 10 speed seal
HP 42
Atk 64
Spd 45
Def 26
Res 21

Blade Fury + 10 speed seal
HP 42
Atk 62
Spd 44
Def 40
Res 35

I'd prefer the blade fury build as that's a nice large chunk of res, xander level def, and a bulk of speed and attack. of course any unit can be drastically OP at 10 merges but the last numbers were to merely show potential.

(I'm F2P ^_-)