Sergi Bruguera used to worship Jimmy Connors as a kid. He was a very tough player to beat on clay as his forehand was very very heavily topspun in the corners and it was at least head high when it got up, on the forehand return he could only block back because of his grip. His backhand wasn't as heavy, but he placed it very well in addition to having great court coverage and sense made him very difficult to beat.
It was because of him, they made the courts at RG a lot quicker, unlike Muster he didn't mind playing serve/volleyers witnessing his great Wimbledon win over Rafter in 94, there is no way he should have won that match. He was also competent on hardcourts, he made finals on the hardcourts, but wasn't able to win them.
Bruguera yes his forehand was unique, but the prototype will always be Kent Carlsson. I mean that is why Muster played so well against Bruguera as he had the practice against the prototype and couldn't beat him.
The funny thing is Bruguera actually beat Sampras on a hardcourt and he beat Rafter on grass at Wimbledon. He made the Miami final, but on the faster surfaces he used the block forehand return exclusively for the reasons you stated. The thing is Bruguera actually didn't mind playing serve/volleyers that was where he was different to Muster
That dreaded thing called injury really stunted his progress. I remember seeing the 96 RG when Sampras beat him in 5 sets. It was obvious that Sergi was lacking in confidence and he tore ankle ligaments at the end of 95 which put him behind schedule and he really needed his fitness to be at its best, as his game was very taxing.
He lost form in 98 and missed nearly all of 99 with shoulder problems, so these were the main reasons.
Don't forget Bruguera was # 4 for two years in a row before he finished at # 13 in 95 that and he had defended his RG crown, he beat Rafter on grass
all in 94. It happens that not every player can have great years and Muster was the king of clay that year that is undisputed and I was very disappointed with his loss in the semis of RG to Chang.
He had injury problems at the start of the year and he missed 6 weeks of tennis after he defaulted in a match against Volkov so that robbed him of his fitness base which is needed for the clay season.
Sergi's forehand was much better as a winning shot, but Bruguera could great length on his two hander and was quite good at passing shots moreso than say Muster for an example. His serve was a heavy kicker which made sense and not always easy to attack.
Volleys he had some very good feel around the net and hit good drop volleys.
Bruguera wasn't just a claycourt specialist. I mean he had a 3-2 record over Sampras. He won the last match at Miami, and the one he lost on carpet he managed to lose 6-3 1-6 6-3, so he got a set off Pete on carpet, so he wasn't too bad.
I remember the ankle problems he had, it was at the Stuttgart indoor and he went the wrong way and you could see the pain in his face. So I wouldn't say the ankle one was down to technique.