In YGOSU, it is mostly agreed upon that when three or more players are playing on team melee, protoss becomes the strongest race due to the likelihood of strong play-making potential from units such as early game harassment from probes having a single player dedicate all his focus on it, corsairs that never die throughout the entire game versus the zergs, and game changing late-game spellcasters such as arbiters.
Now, I am not talking about poorly co-ordinated team melee combinations, but three strong players dividing their roles in an effective manner. The protoss race is almost perfect for such division of labour in my opinion, and benefit the most from RPG elements that are seen from games such as Warcraft 3. While one player takes reign of macro-management duties, top notch protoss players who have honed their craft can make godly plays when left alone to make heroes out of impactful units like reavers, high templars, and arbiters.
There are no accurate objective assessment of someone's mechanics, but there is an objective measurement that does somewhat correlate to a player's mechanical ability, and that is eAPM. The correlation may not be strong, but it is the best objective measurement we have thus far.
If we have a cut-off point of 210 eAPM for what constitutes a fast player more capable than the average professional player in terms of carrying out more number of tasks in a short span of time, then these are the protoss players I have who have regularly hit eAPM averages above 210 in professional games.
1) Bisu's eAPM range from replays gathered from WCG 2009: 232 ~ 252
2) JangBi's eAPM range from replays gathered from Blizzcon 2008: 202 ~ 219
There are literally nobody else that I know who have regularly hit eAPM figures that these two players hit, and these players also happen to be some of the most successful protoss players of all time.
Do the same for the other two races, even if you raise the bar to take into account the higher average eAPM figures for the players of the zerg and terran races, you find anomalies that don't belong:
Sharp's eAPM from a replay gathered from practice: 258
Terror's eAPM from a replay gathered from practice: 251
Cases of extremely fast players (in terms of eAPM), compared to even the very fastest players, having very unproductive professional careers are way more common for the other two races. I don't think I've ever come across a replay of a protoss player with eAPM figures of over 210 during the professional era of Brood War, yet failed to make any mark on the scene.
One of the reasons why the balance tends to shift towards the protoss race in a team melee setting, even against the zerg race, a match-up that is regarded by many as being the most broken in the current meta-game, is due to the fact that separately managed corsairs and shuttle harassment, that does not negatively influence the pace of the macro-management side of things, is an extremely potent combination.
It is one of the reasons, in my opinion, Bisu separates himself from the other protoss players in the zerg match-up. No other protoss players are capable of making good use of their corsairs while keeping up with the mechanical demands of micro-managing the ground army, maintaining macro-management from multiple bases, and doing harassment with shuttles to keep the zerg from growing out of control.
That means that people currently streaming on AfreecaTV, that plays the protoss race, could be ranked by their eAPM averages, and it would be more accurate indicators of their overall performance than it is for the other two races.
I haven't been a regular follower of the AfreecaTV scene, but the general trend seems to be Bisu as the extreme outlier, and others lagging behind.
Bisu: 267 (in a sponsored match versus herO)
As far as I know of, Bisu still is by far the most mechanically talented protoss player in the scene in terms of eAPM. There are other protoss players who have relatively high figures of eAPM like JangBi, Rain, and Mini, but even these guys struggle to get eAPM numbers anywhere near Bisu. Rain and Mini are doing quite well for themselves recently in terms of results, and I hope after some time, JangBi can recover some of his past skills, because he was the only protoss player that somewhat matched Bisu (I actually thought that JangBi had superior mechanics back then, but I currently believe that to be false) in terms of sheer mechanics during his professional days.