I understand that he is part of the group now.
Unless that is incredibly recent news, I'd say better prepare for someone else! Their official website makes no mention of it (as it certainly would had he joined them for even a little tour or a single gig):
https://bloodsweatandtears.com/DCT left BS&T in 2004 (when he moved from New York back to Canada), never to return so far. He still plays BS&T music under his own name.
And he remains connected to the group because he and former drummer-turned-producer Bobby Colomby own the rights to the name (DCT might have relinquished them by now, but Colomby still owns the name), touring BS&T is today basically a franchise with alumni such as Steve Katz sometimes joining them for a few gigs. That is not to say that the current line up (not a single original member among them, but that is not saying much with BS&T who have - according to their own website - seen something like 175 (!) individuals go through their ranks over the decades!) are a bunch of slouches, they are not:
I saw BS&T a couple of years ago in Germany at two summer gigs, one of them opening for Chicago, the other a few weeks later as headliners and even at those two gigs they had two different lead vocalists, one of them more "loungy", the other one younger and more "rocky" (he had been a vocal trainer of Vince Neil). Both were fine singers, but neither could get that idiosyncratic mix of "lounge & rock" right that is/was DCT's trademark.
BST's history is unlikely + convoluted to say the least:
Good read here:
https://variety.com/2023/film/reviews/what-the-hell-happened-to-blood-sweat-and-tears-review-david-clayton-thomas-1235565562/And while I agree with Dave that DCT's stage presence was key for early BS&T's success, his successor Jerry Fisher (before DCT returned to the fold in 1974/75) was a great singer too (with three more than respectable BS&T albums under his belt), wonderful pipes, but a much more demure front man (that's Jerry LaCroix from Edgar Winter's White Trash playing the harp and sax btw, he also sang lead on some songs in that particular line up):
There's people who actually prefer Jerry Fisher to DCT because the latter's pronounced guttural delivery is not to everyone's liking all the time (Al Kooper, whose brainchild the band was before he was ousted after the debut album by Colomby and other band members, could certainly contain himself about DCT's delivery style!
). In traditional rock singer terms, it is probably fair to say that Fisher's pure blues/soul voice offered less cheese ingredient than Thomas' vocals (but what's wrong with a little cheese, especially in a BS&T context?).
That's not to say that DCT's early influences - James Brown anyone?! - were any less black than Fisher's:
Anyway, please report about the gig here, Most Honorable Brother Al, as the resident BS&T nerd here, I'm really curious. I'd love to see them again, their European appearances have become unfortunately rare.