As per ticket #2041, it's impossible to use the "speed enabled" show/hide -functions on table-rows (and actually a few other elements whose native display-mode is not "block"), why even offer the possibility of shooting yourself in the foot? When a developer erroneously attempts to do something like that, why not just silently disallow it; a change could be made (for example) by changing this:
show: function(speed,callback){
return speed ?
...
hide: function(speed,callback){
return speed ?
...into this:
show: function(speed,callback){
return !this.is("tr,td,th") && speed ?
...
hide: function(speed,callback){
return !this.is("tr,td,th") && speed ?
The reason for this suggestion is that when the display-mode is changed from the native ("table-row" for TR, "table-cell" for TD, etc.) into "block", there are some unwanted side-effects in the rendering engines that could propably cause some mayhem in the long run.